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Diffstat (limited to 'vendor/github.com/dsoprea/go-exif/v3/data_layer.go')
-rw-r--r--vendor/github.com/dsoprea/go-exif/v3/data_layer.go50
1 files changed, 50 insertions, 0 deletions
diff --git a/vendor/github.com/dsoprea/go-exif/v3/data_layer.go b/vendor/github.com/dsoprea/go-exif/v3/data_layer.go
new file mode 100644
index 000000000..7883752cc
--- /dev/null
+++ b/vendor/github.com/dsoprea/go-exif/v3/data_layer.go
@@ -0,0 +1,50 @@
+package exif
+
+import (
+ "io"
+
+ "github.com/dsoprea/go-logging"
+ "github.com/dsoprea/go-utility/v2/filesystem"
+)
+
+type ExifBlobSeeker interface {
+ GetReadSeeker(initialOffset int64) (rs io.ReadSeeker, err error)
+}
+
+// ExifReadSeeker knows how to retrieve data from the EXIF blob relative to the
+// beginning of the blob (so, absolute position (0) is the first byte of the
+// EXIF data).
+type ExifReadSeeker struct {
+ rs io.ReadSeeker
+}
+
+func NewExifReadSeeker(rs io.ReadSeeker) *ExifReadSeeker {
+ return &ExifReadSeeker{
+ rs: rs,
+ }
+}
+
+func NewExifReadSeekerWithBytes(exifData []byte) *ExifReadSeeker {
+ sb := rifs.NewSeekableBufferWithBytes(exifData)
+ edbs := NewExifReadSeeker(sb)
+
+ return edbs
+}
+
+// Fork creates a new ReadSeeker instead that wraps a BouncebackReader to
+// maintain its own position in the stream.
+func (edbs *ExifReadSeeker) GetReadSeeker(initialOffset int64) (rs io.ReadSeeker, err error) {
+ defer func() {
+ if state := recover(); state != nil {
+ err = log.Wrap(state.(error))
+ }
+ }()
+
+ br, err := rifs.NewBouncebackReader(edbs.rs)
+ log.PanicIf(err)
+
+ _, err = br.Seek(initialOffset, io.SeekStart)
+ log.PanicIf(err)
+
+ return br, nil
+}