This comment expands all tabs using an 8-character tab-width. You
should ignore this commit when using git blame or use git blame -w.
In the early days, I used to use tabs where possible for indentation,
since emacs did this automatically. In recent years, I have switched
to only using spaces, which means qpdf source code has been a mixture
of spaces and tabs. I have avoided cleaning this up because of not
wanting gratuitous whitespaces change to cloud the output of git
blame, but I changed my mind after discussing with users who view qpdf
source code in editors/IDEs that have other tab widths by default and
in light of the fact that I am planning to start applying automatic
code formatting soon.
Changes from upstream are limited to change #include paths so that I
can place header files and included "c" files in a subdirectory. I
didn't keep the unit tests from sphlib but instead verified them by
running them manually. I will implement the same tests using the
Pl_SHA2 pipeline except that sphlib's sha2 implementation supports
partial bytes, which I will not exercise in qpdf or our tests.
