Our existing libtidy support is based on the legacy "HTML tidy"
project. That project now has a successor called tidy-html5, where all
new features and bugfixes happen. Of particular note are the fixes for
two security vulnerabilities, CVE-2015-5522 and CVE-2015-5523.
The API is largely unchanged in the new project (which is truly the
successor of the original -- not a fork), and so it is almost a
drop-in replacement as far as PHP is concerned. However, one file has
changed in the new project: "buffio.h" has been moved to
"tidybuffio.h".
This commit detects the presence of tidybuffio.h at build time, and
then adjusts the import statement in tidy.c accordingly. The result is
a build that works against either the legacy project or the new
tidy-html5 project, although the test suite for the tidy extension now
fails. Those failures are not critical and will be fixed.
Gentoo-Bug: 561452
Gentoo-Bug: 585474
PHP-Bug: 72379
