OpenSystemsDevelopment / qpdf

…y management and eliminate redundant `dynamic_cast` logic.

…, improving encapsulation and memory management. Remove the now redundant `pushMD5Pipeline` method and streamline MD5 activation.

…line `linearization pass1` logic  when writing pass1 file

…te encryption handling

…mplified pipeline stack management in `QPDFWriter`.

…ify pipeline stack management

Encapsulated pipeline stack management into a dedicated `Pl_stack` class within `QPDFWriter::Members`. Reorganized related methods to streamline and simplify initialization and activation of pipelines, removing redundant code.

…dundant normalization and string unparse logic across multiple write calls.

…ndling, leverage `std::string_view`, and streamline QDF indent logic.

… overloads, streamline QDF handling, and simplify string and trailer writes.

…onsolidate `iterate_rc4` logic, and streamline RC4 key processing.

…arrays with `std::string`, and simplify key computation logic.

…ect `substr` calls, and simplify password handling logic.

…ys with `std::string`, and simplify related password handling logic.

…implify padding logic, and streamline password handling across methods.

…nline previously separate method, and streamline data encoding logic.

…ased logic in `setEncryptionMinimumVersion`, and reduce redundancy across `QPDFWriter` methods.

…ption dictionary generation, and reduce redundancy in encryption handling logic.

… encryption handling, and reduce redundancy across methods.

…`, simplify method signatures, and centralize logic in `QPDF::EncryptionData` for improved maintainability.

…ng in method parameters, and simplify encryption logic for improved maintainability and reduced redundancy.

…uce redundancy, improve maintainability, and streamline parameter handling.

…ling, and improve maintainability.

…Perms_value_V5` methods; inline their logic into `setV5EncryptionParameters` to simplify encryption data processing.

…dom_string`, improve readability of salts and keys handling, and streamline `compute_Perms_value_V5_clear` logic by returning strings directly.

…std::bitset`, reorganizing related methods, and simplifying access to improve clarity and maintainability.

…irectly access encryption parameters for improved clarity and maintainability.

…, transition `interpretCF` to a class method, and eliminate redundant parameter passing for improved clarity and maintainability.

…rs::initialize` and replacing shared pointers with references for improved clarity and maintainability.

…t parameter passing, and improve maintainability. Change static functions and QPDF methods to EncryptionData methods.

Streamlined method definitions, replaced explicit loop counters with range-based loops, and added `final` specifier to class and methods to ensure overriding restrictions. Simplified constructor and member variable initialization.

…ssing to simplify buffer handling

…cess for consistency and readability.

Simplify `readObjectAtOffset` by splitting responsibilities into separate functions: `read_object_start` and a streamlined `readObjectAtOffset`. Remove redundant parameters and improve code readability, ensuring better modularity for object reading operations.

After xref reconstruction treat the input file as suspect and apply sanity checks to all subsequent object reads.

Remove `in_xref_reconstruction` flag and update references to use `reconstructed_xref` for simplified state management during xref processing. Adjust warnings for invalid dictionary keys in test output.

…n/decompression logic. Remove redundant `Buffer` class dependency.

the xref table has been loaded

Enhanced handling of unexpected tokens during xref table reconstruction. Adjusted logic for invalid tokens, ensuring better robustness during PDF parsing of corrupt PDF files.

Implemented stricter sanity checks to  handle unexpected tokens like array/dictionary close and endobj/endstream more effectively. Improved warning messages and handling of corrupt objects to enhance PDF parsing robustness.

Detect corrupt xref streams early to avoid excessive runtime and memory usage.