(in main branch, hn_ncipher.c is already correct)

essentially overwrites itself with the new ENGINE, with the exception of
reference counts, ex_data structures, and other 'admin' elements. However
if the new ENGINE doesn't populate certain elements, there's the risk of
the "dynamic" ENGINE's elements showing through - the "cmd_defns" were just
one of the possibilities. This implements a more comprehensive cleanup.

device. This change enables it for building as a self-contained "dynamic"
ENGINE, to help testing such mechanisms.

directory, trust the building scripts to handle it properly.

empty set.  This prevents engines that do not set the command
definitions themselves to inherit the ones from "dynamic", which would
otherwise be very confusing.

or we get a dependency war in Makefile.ssl

depend on the environment, like the presence of the OpenBSD crypto
device or of Kerberos, do not change the dependencies within OpenSSL.

it to be defined on all platforms whether or not it is of any practical
use on them. This also resolves linker problems on "special" platforms,
such as win32.

Martin Szotkowski.

types.h to ossl_typ.h.

Let's use sk_ENGINE_CLEANUP_ITEM_pop_free() instead.

of the stack, and the (void *) type used in the underlying sk_***
functions.  However, declaring a STACK_OF(type) where type is a *function*
type implicitly involves casts between function pointers and data pointers.
That's a no-no. This changes the ENGINE_CLEANUP handling to use a regular
data type in the stack.

ENGINE redevelopment. The idea had been that "-1" could be used as a
special "ask me later" 'nid' rather than specifying supported cipher and
digest 'nid's up front. However the idea turned out to be pretty broken.

crypto/evp/ into the corresponding ENGINE. This code is currently untested.

testing. Because of the recent changes (see crypto/engine/README), the
"openssl" ENGINE is no longer needed nor is it loaded automatically or by
ENGINE_load_builtin_engines(). So a explicit ENGINE_load_openssl() call is
required by applications or a modification to eng_all.c before this ENGINE
will be used. This change will send output to stderr as/when its
implementations are used.

ENGING_TABLE mechanism. The necessary hooks from crypto/evp/ to use this
will be committed shortly.

ENGINE_TABLE-based stuff - as described in crypto/engine/README.

Associated miscellaneous changes;
 - the previous cipher/digest hooks that hardwired directly to EVP's
   OBJ_NAME-based storage have been backed out. New cipher/digest support
   has been constructed and will be committed shortly.
 - each implementation defines its own ENGINE_load_<name> function now.
 - the "openssl" ENGINE isn't needed or loaded any more.
 - core (not algorithm or class specific) ENGINE code has been split into
   multiple files to increase readability and decrease linker bloat.
 - ENGINE_cpy() has been removed as it wasn't really a good idea in the
   first place and now, because of registration issues, can't be
   meaningfully defined any more.
 - BN_MOD_EXP[_CRT] support is removed as per the README.
 - a bug in enginetest.c has been fixed.

NB: This commit almost certainly breaks compilation until subsequent
changes are committed.

digest support, are on their way. Rather than having gigantic commit log
messages and/or CHANGES entries, this change to the README will serve as an
outline of what it all is and how it all works.

recently. So comments including file names have been fixed, and copyright
notices brought up to "2001" at the same time.

and DH all conditional upon OPENSSL_NO_RSA.

in "types.h" so that very few headers will need to include engine.h,
generally only C files using API functions will need it (reducing
the header dependencies quite a lot).

(Some platforms need _XOPEN_SOURCE and _XOPEN_SOURCE_EXTENDED to get
the declaration, but on other platforms _XOPEN_SOURCE disables
the strdup declaration in <string.h>.)

error strings - the destroy handler functions unload the error strings so
any pending error state referring to them will not attempt to reference
them after the ENGINE has been destroyed.

being enabled or disabled (respectively) for operation. Additionally, each
ENGINE has a constructor function where it can do more 'structural' level
intialisations such as loading error strings, creating "ex_data" indices,
etc. This change introduces a handler function that gives an ENGINE a
corresponding opportunity to cleanup when the ENGINE is being destroyed. It
also adds the "get/set" API functions that control this "destroy" handler
function in an ENGINE.