OpenSystemsDevelopment / qpdf

Replaced raw shared pointers with std::string for `infilename` to improve simplicity and readability. Added a boolean `empty_input` flag to explicitly track empty input cases. Adjusted related logic and function calls accordingly for consistency.

Replaced shared_ptr<char> with std::string for `outfilename` in QPDFJob, simplifying its usage and reducing unnecessary memory management overhead. Updated related conditional checks and logic to align with the updated type. These changes improve code readability and maintainability.

Simplified checks for empty containers and strings across the codebase using the `.empty()` method. This improves code readability and adheres to best practices for checking emptiness.

Thanks to github user @cdosborn for the basic enhancement.

... to remove the /Root /StructTreeRoot and /MarkInfo entries.

Accept --file and --range as named parameters in additional to
allowing positional arguments. This is in preparation for adding
additional flags.

The check for the number of items was in the wrong place.

This commit contains only the manual changes. It is separated for
clarity. This commit would not pass CI because it lacks the automated
changes, which appear in the next commit.

Rather than adding yet another flag that is almost never useful on its
own, just have --remove-restrictions disable digital signatures. The
operations are still separate in the API.

Avd xcsv brvtns.

Now --json-output just changes defaults. Allow output file with --json.

Add additional parameters that will be needed to call QPDF::writeJSON
in partial mode.

When there is no context for writing output or error messages, use the
default logger.

* Replace --create-from-json=file with --json-input, which causes the
  regular input to be treated as json.
* Eliminate --to-json
* In --json=2, bring back "objects" and eliminate "objectinfo". Stream
  data is never present.
* In --json-output=2, write "qpdf-v2" with "objects" and include
  stream data.

Also add stubs for top-level QPDF methods (createFromJSON,
updateFromJSON)

Update getJSON() methods and calls to them

(patrepl and cleanpatch are my own utilities)

patrepl s/PointerHolder/std::shared_ptr/g {include,libqpdf}/qpdf/*.hh
patrepl s/PointerHolder/std::shared_ptr/g libqpdf/*.cc
patrepl s/make_pointer_holder/std::make_shared/g libqpdf/*.cc
patrepl s/make_array_pointer_holder/QUtil::make_shared_array/g libqpdf/*.cc
patrepl s,qpdf/std::shared_ptr,qpdf/PointerHolder, **/*.cc **/*.hh
git restore include/qpdf/PointerHolder.hh
cleanpatch
./format-code

Run this:

for i in  **/*.cc **/*.c **/*.h **/*.hh; do
  clang-format < $i >| $i.new && mv $i.new $i
done