This repository has been archived by the owner on Jan 15, 2024. It is now read-only.
-
Notifications
You must be signed in to change notification settings - Fork 3
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
- Loading branch information
Showing
8 changed files
with
178 additions
and
3 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Binary file not shown.
Binary file not shown.
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,101 @@ | ||
| /* | ||
| exif-terminator | ||
| Copyright (C) 2022 SuperSeriousBusiness [email protected] | ||
| 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 ( | ||
| "encoding/binary" | ||
| "errors" | ||
| "io" | ||
| ) | ||
|
|
||
| const ( | ||
| riffHeaderSize = 4 * 3 | ||
| ) | ||
|
|
||
| var ( | ||
| riffHeader = [4]byte{'R', 'I', 'F', 'F'} | ||
| webpHeader = [4]byte{'W', 'E', 'B', 'P'} | ||
| exifFourcc = [4]byte{'E', 'X', 'I', 'F'} | ||
| xmpFourcc = [4]byte{'X', 'M', 'P', ' '} | ||
|
|
||
| errNoRiffHeader = errors.New("no RIFF header") | ||
| errNoWebpHeader = errors.New("not a WEBP file") | ||
| ) | ||
|
|
||
| type webpVisitor struct { | ||
| writer io.Writer | ||
| doneHeader bool | ||
| } | ||
|
|
||
| func fourCC(b []byte) [4]byte { | ||
| return [4]byte{b[0], b[1], b[2], b[3]} | ||
| } | ||
|
|
||
| func (v *webpVisitor) split(data []byte, atEOF bool) (advance int, token []byte, err error) { | ||
| // parse/write the header first | ||
| if !v.doneHeader { | ||
| if len(data) < riffHeaderSize { | ||
| // need the full header | ||
| return | ||
| } | ||
| if fourCC(data) != riffHeader { | ||
| err = errNoRiffHeader | ||
| return | ||
| } | ||
| if fourCC(data[8:]) != webpHeader { | ||
| err = errNoWebpHeader | ||
| return | ||
| } | ||
| if _, err = v.writer.Write(data[:riffHeaderSize]); err != nil { | ||
| return | ||
| } | ||
| advance += riffHeaderSize | ||
| data = data[riffHeaderSize:] | ||
| v.doneHeader = true | ||
| } | ||
|
|
||
| // need enough for fourcc and size | ||
| if len(data) < 8 { | ||
| return | ||
| } | ||
| size := int64(binary.LittleEndian.Uint32(data[4:])) | ||
| if (size & 1) != 0 { | ||
| // odd chunk size - extra padding byte | ||
| size++ | ||
| } | ||
| // wait until there is enough | ||
| if int64(len(data)-8) < size { | ||
| return | ||
| } | ||
|
|
||
| fourcc := fourCC(data) | ||
| rawChunkData := data[8 : 8+size] | ||
| if fourcc == exifFourcc || fourcc == xmpFourcc { | ||
| // replace exif/xmp with blank | ||
| rawChunkData = make([]byte, size) | ||
| } | ||
|
|
||
| if _, err = v.writer.Write(data[:8]); err == nil { | ||
| if _, err = v.writer.Write(rawChunkData); err == nil { | ||
| advance += 8 + int(size) | ||
| } | ||
| } | ||
|
|
||
| return | ||
| } |