This is our own version of asprintf(). This original code was written by
Mike Frysinger, and I was able to modify it to use our memory helper
functions.
We need a version of this code because it is not available on glibc at
least without defining _GNU_SOURCE, and I would rather not do that.
This is the first step in improving string handling in OpenRC for #207.
In the past, OpenRC was a hybrid of a centralized and file-scope
license/copyright structure.
I followed the instructions from the Software Freedom Law Center [1] to
convert to a Centralized structure where possible, for easier future
maintenance.
[1] https://softwarefreedom.org/resources/2012/ManagingCopyrightInformation.html
Many of these helpers are not special to librc, so split them out so they
can be used in all source trees (including libeinfo).
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
