How to tell Autoconf “require symbol A or B” from LIB?

Question

I\'m trying to configure Postgres 9.5.4 for OpenSSL 1.1.0. Configure is dying because it can\'t find SSL_library_init in OpenSSL 1.1.0. OpenSSL 1.1.0 provides

Answer 1

Something like this should work out for you:

ACCEPT_SSL_LIB="no"
AC_CHECK_LIB(ssl, OPENSSL_init_ssl, [ACCEPT_SSL_LIB="yes"])
AC_CHECK_LIB(ssl, SSL_library_init, [ACCEPT_SSL_LIB="yes"])
AS_IF([test "x$ACCEPT_SSL_LIB" = xno], [AC_MSG_ERROR([library 'ssl' is required for OpenSSL])])

You may need another variable to tell you what init function to call, to set up SSL, unless there's some macro magic in a header file that will actually fix it up to the right value.