Dependencies for packages exposing OpenSSL binary interface to Perl code
========================================================================

This information is only relevant for maintainers of Debian packages
of Perl XS modules dealing with OpenSSL.

Packages exposing libssl binary objects like SSL_CTX struct pointers
to Perl code need to be compiled against the same version of OpenSSL to
avoid binary incompatibility issues. See <https://bugs.debian.org/848113>.

Compatibility can be ensured by depending on the "perl-openssl-abi-x"
virtual package, where the name is dynamically generated from the SONAME
of the libssl.so symlink included in the libssl-dev package. There can
be only one such package on the system at a time, so this guarantees
that all the installed packages share the same compatibility level.

To generate this dependency, please build-depend on perl-openssl-defaults
and do one of the following:

debhelper using dh:

Use the "perl_openssl" addon and ensure ${perl:Depends} is used in
debian/control.

The debian/rules file might look as follows:

  #!/usr/bin/make -f
  %:
          dh $@ --with perl_openssl

Alternatively, since perl-openssl-defaults/4 you can just build depend
on dh-sequence-perl-openssl and omit the "--with perl_openssl" part.

old-style debhelper:

Run dh_perl_openssl after dh_perl and ensure ${perl:Depends} is used in
debian/control.

packages not using debhelper:

Include /usr/share/perl-openssl-defaults/perl-openssl.make in debian
rules and use PERL_OPENSSL_ABI_VERSION.