Replace operator== and operator!=, which were testing for the same
underlying object, with isSameObjectAs. This change was motivated by
the fact that pikepdf internally had its own operator== method for
QPDFObjectHandle that did structural comparison. I backed out qpdf's
operator== as a courtesy to pikepdf (in my own testing) but also
because I think people might naturally assume that operator== does a
structural comparison, and isSameObjectAs is clearer in its intent.
QPDFValueProxy wasn't a good name for it. We decided the evil of
having the header file be named QPDFObject_private.hh was less than
the evil of having the class be named something other than what it
should have been named.
I decided that it's actually fine to copy a direct object to another
QPDF. Even if we eventually prevent a QPDFObject from having multiple
parents, this could happen if an object is moved.
When a QPDF is destroyed, changing indirect objects to direct nulls
makes them effectively disappear silently when they sneak into other
places. Instead, we should treat this as an error. Adding a destroyed
object type makes this possible.
The qpdf member was already sufficient. Removing this actually fixed a
few pre-existing issues around detecting foreign ownership and
allowing certain conditions to be warnings rather than exceptions.
This is in preparation for restoring a QPDFObject.hh to ease the
transition on qpdf_object_type_e.
This commit was created by
* Renaming QPDFObject.cc and QPDFObject.hh
* Replacing QPDFObject\b with QPDFValueProxy (where \b is word
boundary)
* Running format-code
* Manually resorting files in libqpdf/CMakeLists.txt
* Manually refilling the comment in QPDF.hh near class Resolver
Since Buffer has always implemented its copy constructor with a deep
copy, its Members object will never have multiple owners. Change to unique_ptr.
Also implement move constructors for Buffer, since there may be cases
where a deep copy is not needed.
On destruction of the QPDF object replace all indirect object references
with direct nulls.
Remove all existing code to release resolved references.
Fixes performance issue due to interaction of resetting QPDFValue::qpdf and
og members and prior code.
Also, modify QPDFObject::swapWith to update the ObjGens of the swapped
objects.
Modify QPDF::newIndirect and QPDF::updateCache to keep object ObjGens
up to date.
Also change QPDF::replaceObject and QPDF::swapObjects such that the
QPDFObject assigned to an og in the obj_cache is never replaced; only
QPDFObject::value is updated.
