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Diffstat (limited to 'vendor/codeberg.org/superseriousbusiness/exif-terminator/png.go')
-rw-r--r--vendor/codeberg.org/superseriousbusiness/exif-terminator/png.go93
1 files changed, 0 insertions, 93 deletions
diff --git a/vendor/codeberg.org/superseriousbusiness/exif-terminator/png.go b/vendor/codeberg.org/superseriousbusiness/exif-terminator/png.go
deleted file mode 100644
index 774ec0ed6..000000000
--- a/vendor/codeberg.org/superseriousbusiness/exif-terminator/png.go
+++ /dev/null
@@ -1,93 +0,0 @@
-/*
- exif-terminator
- Copyright (C) 2022 SuperSeriousBusiness admin@gotosocial.org
-
- This program is free software: you can redistribute it and/or modify
- it under the terms of the GNU Affero General Public License as published by
- the Free Software Foundation, either version 3 of the License, or
- (at your option) any later version.
-
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU Affero General Public License for more details.
-
- You should have received a copy of the GNU Affero General Public License
- along with this program. If not, see <http://www.gnu.org/licenses/>.
-*/
-
-package terminator
-
-import (
- "io"
-
- pngstructure "github.com/superseriousbusiness/go-png-image-structure/v2"
-)
-
-type pngVisitor struct {
- ps *pngstructure.PngSplitter
- writer io.Writer
- lastWrittenChunk int
-}
-
-func (v *pngVisitor) split(data []byte, atEOF bool) (int, []byte, error) {
- // execute the ps split function to read in data
- advance, token, err := v.ps.Split(data, atEOF)
- if err != nil {
- return advance, token, err
- }
-
- // if we haven't written anything at all yet, then write the png header back into the writer first
- if v.lastWrittenChunk == -1 {
- if _, err := v.writer.Write(pngstructure.PngSignature[:]); err != nil {
- return advance, token, err
- }
- }
-
- // Check if the splitter now has
- // any new chunks in it for us.
- chunkSlice, err := v.ps.Chunks()
- if err != nil {
- return advance, token, err
- }
-
- // Write each chunk by passing it
- // through our custom write func,
- // which strips out exif and fixes
- // the CRC of each chunk.
- chunks := chunkSlice.Chunks()
- for i, chunk := range chunks {
- if i <= v.lastWrittenChunk {
- // Skip already
- // written chunks.
- continue
- }
-
- // Write this new chunk.
- if err := v.writeChunk(chunk); err != nil {
- return advance, token, err
- }
- v.lastWrittenChunk = i
-
- // Zero data; here you
- // go garbage collector.
- chunk.Data = nil
- }
-
- return advance, token, err
-}
-
-func (v *pngVisitor) writeChunk(chunk *pngstructure.Chunk) error {
- if chunk.Type == pngstructure.EXifChunkType {
- // Replace exif data
- // with zero bytes.
- clear(chunk.Data)
- }
-
- // Fix CRC of each chunk.
- chunk.UpdateCrc32()
-
- // finally, write chunk to writer.
- _, err := chunk.WriteTo(v.writer)
- return err
-}