Account for inaccurate offsets in getXrefData() #692
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Normally offset pointers to `xref` keywords in a PDF document are exact to the byte. However, in some cases the pointer may point to some whitespace *before* the `xref` keyword. Adobe Acrobat takes these 'errors' in stride, displaying the document anyway, and so should PdfParser. Clean up the getXrefData() function in **RawDataParser.php**. It now only needs to do one `preg_match_all()` and pushes the caret past whitespace when looking for `xref` keywords. Use existing **Issue557.pdf** to create a new file: **Issue673.pdf** where the last `/Prev 13486` command has been decremented to `/Prev 13485`. Trying to parse this file would cause an Exception without this fix.
k00ni
requested changes
Mar 25, 2024
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Thank you @GreyWyvern, good work! I have just a few remarks/questions.
No need to use `PREG_OFFSET_CAPTURE` here.
k00ni
approved these changes
Apr 2, 2024
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Normally offset pointers to
xrefkeywords in a PDF document are exact to the byte. However, in some cases the pointer may point to some whitespace before thexrefkeyword. Adobe Acrobat takes these 'errors' in stride, displaying the document anyway, and so should PdfParser.Clean up the getXrefData() function in RawDataParser.php. It now only needs to do one
preg_match_all()and pushes the caret past whitespace when looking forxrefkeywords.Use existing Issue557.pdf to create a new file: Issue673.pdf where the last
/Prev 13486command has been decremented to/Prev 13485. Trying to parse this file would cause an Exception without this fix. Resolves #673.Checklist for code / configuration changes
In case you changed the code/configuration, please read each of the following checkboxes as they contain valuable information:
fixes #1234to outline that you are providing a fix for the issue#1234.