Modeled on QByteArrayData/QStringData/QVectorData, the intent is to
unify book-keeping structs for array-like data and enable sharing of
code among them.
As in those structures, size (and alloc) data member(s) specify the
number of *typed* elements the array does (and can) hold. The size or
alignment requirements of those objects is not tracked in this data
structure and needs to be maintained by its users.
Contrary to QByteArrayData and QStringData, QArrayData's offset member
keeps a *byte* offset to the actual data array and is computed from the
beginning of the struct.
Shared-null and -empty functionality is provided by QArrayData and
shared among all users.
Planned features include setSharable (force deep copies), fromRawData
(detached header and data allocations) and literals a la QStringLiteral
(static immutable instances), thus covering the functionality needed for
QByteArray, QString and QVector.
Change-Id: I9aa709dbb675442e6d06965efb8138ab84602bbd
Reviewed-by: Bradley T. Hughes <bradley.hughes@nokia.com>
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>