master 88795c5 3/3: Have gnutls_symmetric cache the results from Fgnutls_ciphers

[Lars Ingebrigtsen]

branch: master
commit 88795c52ff13203dda5940ed5defc26ce2c20e5e
Author: Lars Ingebrigtsen <larsi@gnus.org>
Commit: Lars Ingebrigtsen <larsi@gnus.org>

    Have gnutls_symmetric cache the results from Fgnutls_ciphers
    
    * src/gnutls.c (gnutls_symmetric): Cache the results from
    Fgnutls_ciphers, since that function isn't very fast (bug#42998).
    (syms_of_gnutls): Initialize cache variable.
---
 src/gnutls.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/gnutls.c b/src/gnutls.c
index 416fb15..0010553 100644
--- a/src/gnutls.c
+++ b/src/gnutls.c
@@ -2298,6 +2298,8 @@ gnutls_symmetric_aead (bool encrypting, 
gnutls_cipher_algorithm_t gca,
 # endif
 }
 
+static Lisp_Object cipher_cache;
+
 static Lisp_Object
 gnutls_symmetric (bool encrypting, Lisp_Object cipher,
                   Lisp_Object key, Lisp_Object iv,
@@ -2329,7 +2331,9 @@ gnutls_symmetric (bool encrypting, Lisp_Object cipher,
 
   if (SYMBOLP (cipher))
     {
-      info = Fassq (cipher, Fgnutls_ciphers ());
+      if (NILP (cipher_cache))
+       cipher_cache = Fgnutls_ciphers ();
+      info = Fassq (cipher, cipher_cache);
       if (!CONSP (info))
        xsignal2 (Qerror,
                  build_string ("GnuTLS cipher is invalid or not found"),
@@ -2914,6 +2918,9 @@ level in the ones.  For builds without libgnutls, the 
value is -1.  */);
   defsubr (&Sgnutls_hash_digest);
   defsubr (&Sgnutls_symmetric_encrypt);
   defsubr (&Sgnutls_symmetric_decrypt);
+
+  cipher_cache = Qnil;
+  staticpro (&cipher_cache);
 #endif
 
   DEFVAR_INT ("gnutls-log-level", global_gnutls_log_level,