diff options
Diffstat (limited to 'vendor/github.com/godbus/dbus/v5/sig.go')
-rw-r--r-- | vendor/github.com/godbus/dbus/v5/sig.go | 259 |
1 files changed, 259 insertions, 0 deletions
diff --git a/vendor/github.com/godbus/dbus/v5/sig.go b/vendor/github.com/godbus/dbus/v5/sig.go new file mode 100644 index 000000000..c1b809202 --- /dev/null +++ b/vendor/github.com/godbus/dbus/v5/sig.go @@ -0,0 +1,259 @@ +package dbus + +import ( + "fmt" + "reflect" + "strings" +) + +var sigToType = map[byte]reflect.Type{ + 'y': byteType, + 'b': boolType, + 'n': int16Type, + 'q': uint16Type, + 'i': int32Type, + 'u': uint32Type, + 'x': int64Type, + 't': uint64Type, + 'd': float64Type, + 's': stringType, + 'g': signatureType, + 'o': objectPathType, + 'v': variantType, + 'h': unixFDIndexType, +} + +// Signature represents a correct type signature as specified by the D-Bus +// specification. The zero value represents the empty signature, "". +type Signature struct { + str string +} + +// SignatureOf returns the concatenation of all the signatures of the given +// values. It panics if one of them is not representable in D-Bus. +func SignatureOf(vs ...interface{}) Signature { + var s string + for _, v := range vs { + s += getSignature(reflect.TypeOf(v)) + } + return Signature{s} +} + +// SignatureOfType returns the signature of the given type. It panics if the +// type is not representable in D-Bus. +func SignatureOfType(t reflect.Type) Signature { + return Signature{getSignature(t)} +} + +// getSignature returns the signature of the given type and panics on unknown types. +func getSignature(t reflect.Type) string { + // handle simple types first + switch t.Kind() { + case reflect.Uint8: + return "y" + case reflect.Bool: + return "b" + case reflect.Int16: + return "n" + case reflect.Uint16: + return "q" + case reflect.Int, reflect.Int32: + if t == unixFDType { + return "h" + } + return "i" + case reflect.Uint, reflect.Uint32: + if t == unixFDIndexType { + return "h" + } + return "u" + case reflect.Int64: + return "x" + case reflect.Uint64: + return "t" + case reflect.Float64: + return "d" + case reflect.Ptr: + return getSignature(t.Elem()) + case reflect.String: + if t == objectPathType { + return "o" + } + return "s" + case reflect.Struct: + if t == variantType { + return "v" + } else if t == signatureType { + return "g" + } + var s string + for i := 0; i < t.NumField(); i++ { + field := t.Field(i) + if field.PkgPath == "" && field.Tag.Get("dbus") != "-" { + s += getSignature(t.Field(i).Type) + } + } + return "(" + s + ")" + case reflect.Array, reflect.Slice: + return "a" + getSignature(t.Elem()) + case reflect.Map: + if !isKeyType(t.Key()) { + panic(InvalidTypeError{t}) + } + return "a{" + getSignature(t.Key()) + getSignature(t.Elem()) + "}" + case reflect.Interface: + return "v" + } + panic(InvalidTypeError{t}) +} + +// ParseSignature returns the signature represented by this string, or a +// SignatureError if the string is not a valid signature. +func ParseSignature(s string) (sig Signature, err error) { + if len(s) == 0 { + return + } + if len(s) > 255 { + return Signature{""}, SignatureError{s, "too long"} + } + sig.str = s + for err == nil && len(s) != 0 { + err, s = validSingle(s, 0) + } + if err != nil { + sig = Signature{""} + } + + return +} + +// ParseSignatureMust behaves like ParseSignature, except that it panics if s +// is not valid. +func ParseSignatureMust(s string) Signature { + sig, err := ParseSignature(s) + if err != nil { + panic(err) + } + return sig +} + +// Empty retruns whether the signature is the empty signature. +func (s Signature) Empty() bool { + return s.str == "" +} + +// Single returns whether the signature represents a single, complete type. +func (s Signature) Single() bool { + err, r := validSingle(s.str, 0) + return err != nil && r == "" +} + +// String returns the signature's string representation. +func (s Signature) String() string { + return s.str +} + +// A SignatureError indicates that a signature passed to a function or received +// on a connection is not a valid signature. +type SignatureError struct { + Sig string + Reason string +} + +func (e SignatureError) Error() string { + return fmt.Sprintf("dbus: invalid signature: %q (%s)", e.Sig, e.Reason) +} + +// Try to read a single type from this string. If it was successful, err is nil +// and rem is the remaining unparsed part. Otherwise, err is a non-nil +// SignatureError and rem is "". depth is the current recursion depth which may +// not be greater than 64 and should be given as 0 on the first call. +func validSingle(s string, depth int) (err error, rem string) { + if s == "" { + return SignatureError{Sig: s, Reason: "empty signature"}, "" + } + if depth > 64 { + return SignatureError{Sig: s, Reason: "container nesting too deep"}, "" + } + switch s[0] { + case 'y', 'b', 'n', 'q', 'i', 'u', 'x', 't', 'd', 's', 'g', 'o', 'v', 'h': + return nil, s[1:] + case 'a': + if len(s) > 1 && s[1] == '{' { + i := findMatching(s[1:], '{', '}') + if i == -1 { + return SignatureError{Sig: s, Reason: "unmatched '{'"}, "" + } + i++ + rem = s[i+1:] + s = s[2:i] + if err, _ = validSingle(s[:1], depth+1); err != nil { + return err, "" + } + err, nr := validSingle(s[1:], depth+1) + if err != nil { + return err, "" + } + if nr != "" { + return SignatureError{Sig: s, Reason: "too many types in dict"}, "" + } + return nil, rem + } + return validSingle(s[1:], depth+1) + case '(': + i := findMatching(s, '(', ')') + if i == -1 { + return SignatureError{Sig: s, Reason: "unmatched ')'"}, "" + } + rem = s[i+1:] + s = s[1:i] + for err == nil && s != "" { + err, s = validSingle(s, depth+1) + } + if err != nil { + rem = "" + } + return + } + return SignatureError{Sig: s, Reason: "invalid type character"}, "" +} + +func findMatching(s string, left, right rune) int { + n := 0 + for i, v := range s { + if v == left { + n++ + } else if v == right { + n-- + } + if n == 0 { + return i + } + } + return -1 +} + +// typeFor returns the type of the given signature. It ignores any left over +// characters and panics if s doesn't start with a valid type signature. +func typeFor(s string) (t reflect.Type) { + err, _ := validSingle(s, 0) + if err != nil { + panic(err) + } + + if t, ok := sigToType[s[0]]; ok { + return t + } + switch s[0] { + case 'a': + if s[1] == '{' { + i := strings.LastIndex(s, "}") + t = reflect.MapOf(sigToType[s[2]], typeFor(s[3:i])) + } else { + t = reflect.SliceOf(typeFor(s[1:])) + } + case '(': + t = interfacesType + } + return +} |