1 files changed, 85 insertions, 0 deletions
diff --git a/vendor/github.com/superseriousbusiness/go-png-image-structure/v2/media_parser.go b/vendor/github.com/superseriousbusiness/go-png-image-structure/v2/media_parser.go
new file mode 100644
index 000000000..4c8421905
--- /dev/null
+++ b/vendor/github.com/superseriousbusiness/go-png-image-structure/v2/media_parser.go
@@ -0,0 +1,85 @@
+package pngstructure
+
+import (
+	"bufio"
+	"bytes"
+	"image"
+	"io"
+	"os"
+
+	"image/png"
+
+	riimage "github.com/dsoprea/go-utility/v2/image"
+)
+
+// PngMediaParser knows how to parse a PNG stream.
+type PngMediaParser struct {
+}
+
+// NewPngMediaParser returns a new `PngMediaParser`.
+func NewPngMediaParser() riimage.MediaParser {
+	return new(PngMediaParser)
+}
+
+// Parse parses a PNG stream given a `io.ReadSeeker`.
+func (pmp *PngMediaParser) Parse(
+	rs io.ReadSeeker,
+	size int,
+) (riimage.MediaContext, error) {
+	ps := NewPngSplitter()
+	if err := ps.readHeader(rs); err != nil {
+		return nil, err
+	}
+
+	s := bufio.NewScanner(rs)
+
+	// Since each segment can be any
+	// size, our buffer must be allowed
+	// to grow as large as the file.
+	buffer := []byte{}
+	s.Buffer(buffer, size)
+	s.Split(ps.Split)
+
+	for s.Scan() {
+	}
+
+	if err := s.Err(); err != nil {
+		return nil, err
+	}
+
+	return ps.Chunks()
+}
+
+// ParseFile parses a PNG stream given a file-path.
+func (pmp *PngMediaParser) ParseFile(filepath string) (riimage.MediaContext, error) {
+	f, err := os.Open(filepath)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	stat, err := f.Stat()
+	if err != nil {
+		return nil, err
+	}
+
+	size := stat.Size()
+	return pmp.Parse(f, int(size))
+}
+
+// ParseBytes parses a PNG stream given a byte-slice.
+func (pmp *PngMediaParser) ParseBytes(data []byte) (riimage.MediaContext, error) {
+	br := bytes.NewReader(data)
+	return pmp.Parse(br, len(data))
+}
+
+// LooksLikeFormat returns a boolean indicating
+// whether the stream looks like a PNG image.
+func (pmp *PngMediaParser) LooksLikeFormat(data []byte) bool {
+	return bytes.Equal(data[:len(PngSignature)], PngSignature[:])
+}
+
+// GetImage returns an image.Image-compatible struct.
+func (pmp *PngMediaParser) GetImage(r io.Reader) (img image.Image, err error) {
+	return png.Decode(r)
+}