functions on platform were that's the best way to handle exporting
global variables in shared libraries. To enable this functionality,
one must configure with "EXPORT_VAR_AS_FN" or defined the C macro
"OPENSSL_EXPORT_VAR_AS_FUNCTION" in crypto/opensslconf.h (the latter
is normally done by Configure or something similar).
To implement a global variable, use the macro OPENSSL_IMPLEMENT_GLOBAL
in the source file (foo.c) like this:
OPENSSL_IMPLEMENT_GLOBAL(int,foo)=1;
OPENSSL_IMPLEMENT_GLOBAL(double,bar);
To declare a global variable, use the macros OPENSSL_DECLARE_GLOBAL
and OPENSSL_GLOBAL_REF in the header file (foo.h) like this:
OPENSSL_DECLARE_GLOBAL(int,foo);
#define foo OPENSSL_GLOBAL_REF(foo)
OPENSSL_DECLARE_GLOBAL(double,bar);
#define bar OPENSSL_GLOBAL_REF(bar)
The #defines are very important, and therefore so is including the
header file everywere where the defined globals are used.
The macro OPENSSL_EXPORT_VAR_AS_FUNCTION also affects the definition
of ASN.1 items, but that structure is a bt different.
The largest change is in util/mkdef.pl which has been enhanced with
better and easier to understand logic to choose which symbols should
go into the Windows .def files as well as a number of fixes and code
cleanup (among others, algorithm keywords are now sorted
lexicographically to avoid constant rewrites).
handlers were previously getting called before (and after, respectively)
the "ex_data" structures - this meant init() had very little that it
could initialise, and finish() had very little it could cleanup.
change the way ASN1 modules are exported.
Still needs a bit of work for example the hack which a
dummy function prototype to avoid compilers warning about
multiple ;s.
an SSL_CTX's session cache, it is necessary to compare the ssl_version at
the same time (a conflict is defined, courtesy of SSL_SESSION_cmp(), as a
matching id/id_length pair and a matching ssl_version). However, the
SSL_SESSION that will result from the current negotiation does not
necessarily have the same ssl version as the "SSL_METHOD" in use by the
SSL_CTX - part of the work in a handshake is to agree on an ssl version!
This is fixed by having the check function accept an SSL pointer rather
than the SSL_CTX it belongs to.
[Thanks to Lutz for illuminating the full extent of my stupidity]
really see why we need to define these function pointers with MS_FAR
if it's not done cosistently everywhere.
If we decide to support MS_FAR modifiers, it's better to have the
named something more unique for OpenSSL and to define them in e_os2.h.
and make all files the depend on it include it without prefixing it
with openssl/.
This means that all Makefiles will have $(TOP) as one of the include
directories.
