Add CoreTokenScanner.ClearPreReadByte() and further fix #1332#1334
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This was referenced Jun 25, 2026
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Commit 9c9cb41 added % to the
PlainTokenizerbreak set so a comment immediately following a keyword/operator terminates the token, which matches ISO 32000-2 §7.2.3–7.2.4 and pdfbox'sBaseParser.isEndOfName(which likewise treats % as a delimiter).That change exposed a latent bug: PdfPig's
CoreTokenScannerkeeps a persistent look-ahead byte (hasBytePreRead)that was not discarded onSeek, so after jumping to an object's xref offset the scanner began reading one byte late and failed, triggering a spurious brute-force scan during the still-NoOp encryption phase that cached objects undecrypted.The fix adds
CoreTokenScanner.ClearPreReadByte()and calls it after the seeks inPdfTokenScanner.GetandTryBruteForceFileToFindReference,so the next read starts exactly at the sought byte. This mirrors pdfbox, whoseparseFileObjectdoessource.seek(objOffset)and immediately reads from that offset using read-then-rewind(1) look-ahead, meaning no byte is ever carried across a seek.