londonCyclist opened a new issue, #1018:
URL: https://github.com/apache/poi/issues/1018
Tested with version 5.5.1 , local file header (LOC) generated while using
SXSSFWorkbook with zip64 mode is not set as per the spec (6.3.9) given below;
https://pkwaredownloads.blob.core.windows.net/pkware-general/Documentation/APPNOTE-6.3.9.TXT
```
4.3.9.2 When compressing files, compressed and uncompressed sizes
SHOULD be stored in ZIP64 format (as 8 byte values) when a
file's size exceeds 0xFFFFFFFF. **_However ZIP64 format MAY be
used regardless of the size of a file. When extracting, if
the zip64 extended information extra field is present for
the file the compressed and uncompressed sizes will be 8
byte values._**
```
I was expecting zip64 extended information extra field to be present in LOC
header when compressed and uncompressed sizes were represented as 8 bytes in
the data directory record. As a result the application reading data directory
record will endup reading it in zip32 mode, this results in both compressed and
uncompressed size to be incorrect.
<img width="1076" height="107" alt="Image"
src="https://github.com/user-attachments/assets/945bbad5-d520-4b02-95e3-c242127d70dd";
/>
Fig 1: Local file header
extended information extra field is not set (purple) , CRC (green) ,
compressed size (orange) , uncompressed size(red)
<img width="1076" height="107" alt="Image"
src="https://github.com/user-attachments/assets/ad154c48-e699-480a-ba47-75ab429c4752";
/>
Fig 2: Data directory record
Reading application has no way to determine if the data directory record is
represented in Zip32 or Zip64 mode .
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