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author | Sebastian P <5564491+s3lph@users.noreply.github.com> | 2020-10-01 22:50:56 +0200 |
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committer | GitHub <noreply@github.com> | 2020-10-01 22:50:56 +0200 |
commit | 214a6a13861b9fd495797386f36507373728e577 (patch) | |
tree | a2eb9541924b432ecf7a0807f42281296fa144a4 /vendor/github.com/vincent-petithory/dataurl/dataurl.go | |
parent | e7781dc79c0c556f60eb64a93a95a5da494dcf2d (diff) | |
download | matterbridge-msglm-214a6a13861b9fd495797386f36507373728e577.tar.gz matterbridge-msglm-214a6a13861b9fd495797386f36507373728e577.tar.bz2 matterbridge-msglm-214a6a13861b9fd495797386f36507373728e577.zip |
Add Mumble support (#1245)
Diffstat (limited to 'vendor/github.com/vincent-petithory/dataurl/dataurl.go')
-rw-r--r-- | vendor/github.com/vincent-petithory/dataurl/dataurl.go | 291 |
1 files changed, 291 insertions, 0 deletions
diff --git a/vendor/github.com/vincent-petithory/dataurl/dataurl.go b/vendor/github.com/vincent-petithory/dataurl/dataurl.go new file mode 100644 index 00000000..7a9fe67e --- /dev/null +++ b/vendor/github.com/vincent-petithory/dataurl/dataurl.go @@ -0,0 +1,291 @@ +package dataurl + +import ( + "bytes" + "encoding/base64" + "errors" + "fmt" + "io" + "io/ioutil" + "net/http" + "sort" + "strconv" + "strings" +) + +const ( + // EncodingBase64 is base64 encoding for the data url + EncodingBase64 = "base64" + // EncodingASCII is ascii encoding for the data url + EncodingASCII = "ascii" +) + +func defaultMediaType() MediaType { + return MediaType{ + "text", + "plain", + map[string]string{"charset": "US-ASCII"}, + } +} + +// MediaType is the combination of a media type, a media subtype +// and optional parameters. +type MediaType struct { + Type string + Subtype string + Params map[string]string +} + +// ContentType returns the content type of the dataurl's data, in the form type/subtype. +func (mt *MediaType) ContentType() string { + return fmt.Sprintf("%s/%s", mt.Type, mt.Subtype) +} + +// String implements the Stringer interface. +// +// Params values are escaped with the Escape function, rather than in a quoted string. +func (mt *MediaType) String() string { + var ( + buf bytes.Buffer + keys = make([]string, len(mt.Params)) + i int + ) + for k := range mt.Params { + keys[i] = k + i++ + } + sort.Strings(keys) + for _, k := range keys { + v := mt.Params[k] + fmt.Fprintf(&buf, ";%s=%s", k, EscapeString(v)) + } + return mt.ContentType() + (&buf).String() +} + +// DataURL is the combination of a MediaType describing the type of its Data. +type DataURL struct { + MediaType + Encoding string + Data []byte +} + +// New returns a new DataURL initialized with data and +// a MediaType parsed from mediatype and paramPairs. +// mediatype must be of the form "type/subtype" or it will panic. +// paramPairs must have an even number of elements or it will panic. +// For more complex DataURL, initialize a DataURL struct. +// The DataURL is initialized with base64 encoding. +func New(data []byte, mediatype string, paramPairs ...string) *DataURL { + parts := strings.Split(mediatype, "/") + if len(parts) != 2 { + panic("dataurl: invalid mediatype") + } + + nParams := len(paramPairs) + if nParams%2 != 0 { + panic("dataurl: requires an even number of param pairs") + } + params := make(map[string]string) + for i := 0; i < nParams; i += 2 { + params[paramPairs[i]] = paramPairs[i+1] + } + + mt := MediaType{ + parts[0], + parts[1], + params, + } + return &DataURL{ + MediaType: mt, + Encoding: EncodingBase64, + Data: data, + } +} + +// String implements the Stringer interface. +// +// Note: it doesn't guarantee the returned string is equal to +// the initial source string that was used to create this DataURL. +// The reasons for that are: +// * Insertion of default values for MediaType that were maybe not in the initial string, +// * Various ways to encode the MediaType parameters (quoted string or url encoded string, the latter is used), +func (du *DataURL) String() string { + var buf bytes.Buffer + du.WriteTo(&buf) + return (&buf).String() +} + +// WriteTo implements the WriterTo interface. +// See the note about String(). +func (du *DataURL) WriteTo(w io.Writer) (n int64, err error) { + var ni int + ni, _ = fmt.Fprint(w, "data:") + n += int64(ni) + + ni, _ = fmt.Fprint(w, du.MediaType.String()) + n += int64(ni) + + if du.Encoding == EncodingBase64 { + ni, _ = fmt.Fprint(w, ";base64") + n += int64(ni) + } + + ni, _ = fmt.Fprint(w, ",") + n += int64(ni) + + if du.Encoding == EncodingBase64 { + encoder := base64.NewEncoder(base64.StdEncoding, w) + ni, err = encoder.Write(du.Data) + if err != nil { + return + } + encoder.Close() + } else if du.Encoding == EncodingASCII { + ni, _ = fmt.Fprint(w, Escape(du.Data)) + n += int64(ni) + } else { + err = fmt.Errorf("dataurl: invalid encoding %s", du.Encoding) + return + } + + return +} + +// UnmarshalText decodes a Data URL string and sets it to *du +func (du *DataURL) UnmarshalText(text []byte) error { + decoded, err := DecodeString(string(text)) + if err != nil { + return err + } + *du = *decoded + return nil +} + +// MarshalText writes du as a Data URL +func (du *DataURL) MarshalText() ([]byte, error) { + buf := bytes.NewBuffer(nil) + if _, err := du.WriteTo(buf); err != nil { + return nil, err + } + return buf.Bytes(), nil +} + +type encodedDataReader func(string) ([]byte, error) + +var asciiDataReader encodedDataReader = func(s string) ([]byte, error) { + us, err := Unescape(s) + if err != nil { + return nil, err + } + return []byte(us), nil +} + +var base64DataReader encodedDataReader = func(s string) ([]byte, error) { + data, err := base64.StdEncoding.DecodeString(s) + if err != nil { + return nil, err + } + return []byte(data), nil +} + +type parser struct { + du *DataURL + l *lexer + currentAttr string + unquoteParamVal bool + encodedDataReaderFn encodedDataReader +} + +func (p *parser) parse() error { + for item := range p.l.items { + switch item.t { + case itemError: + return errors.New(item.String()) + case itemMediaType: + p.du.MediaType.Type = item.val + // Should we clear the default + // "charset" parameter at this point? + delete(p.du.MediaType.Params, "charset") + case itemMediaSubType: + p.du.MediaType.Subtype = item.val + case itemParamAttr: + p.currentAttr = item.val + case itemLeftStringQuote: + p.unquoteParamVal = true + case itemParamVal: + val := item.val + if p.unquoteParamVal { + p.unquoteParamVal = false + us, err := strconv.Unquote("\"" + val + "\"") + if err != nil { + return err + } + val = us + } else { + us, err := UnescapeToString(val) + if err != nil { + return err + } + val = us + } + p.du.MediaType.Params[p.currentAttr] = val + case itemBase64Enc: + p.du.Encoding = EncodingBase64 + p.encodedDataReaderFn = base64DataReader + case itemDataComma: + if p.encodedDataReaderFn == nil { + p.encodedDataReaderFn = asciiDataReader + } + case itemData: + reader, err := p.encodedDataReaderFn(item.val) + if err != nil { + return err + } + p.du.Data = reader + case itemEOF: + if p.du.Data == nil { + p.du.Data = []byte("") + } + return nil + } + } + panic("EOF not found") +} + +// DecodeString decodes a Data URL scheme string. +func DecodeString(s string) (*DataURL, error) { + du := &DataURL{ + MediaType: defaultMediaType(), + Encoding: EncodingASCII, + } + + parser := &parser{ + du: du, + l: lex(s), + } + if err := parser.parse(); err != nil { + return nil, err + } + return du, nil +} + +// Decode decodes a Data URL scheme from a io.Reader. +func Decode(r io.Reader) (*DataURL, error) { + data, err := ioutil.ReadAll(r) + if err != nil { + return nil, err + } + return DecodeString(string(data)) +} + +// EncodeBytes encodes the data bytes into a Data URL string, using base 64 encoding. +// +// The media type of data is detected using http.DetectContentType. +func EncodeBytes(data []byte) string { + mt := http.DetectContentType(data) + // http.DetectContentType may add spurious spaces between ; and a parameter. + // The canonical way is to not have them. + cleanedMt := strings.Replace(mt, "; ", ";", -1) + + return New(data, cleanedMt).String() +} |