gpg: New caching functions.

* g10/objcache.c: New.
* g10/objcache.h: New.
* g10/Makefile.am (common_source): Add them.
* g10/gpg.c: Include objcache.h.
(g10_exit): Call objcache_dump_stats.
* g10/getkey.c: Include objcache.h.
(get_primary_uid, release_keyid_list): Remove.
(cache_user_id): Remove.
(finish_lookup): Call the new cache_put_keyblock instead of
cache_user_id.
(get_user_id_string): Remove code for mode 2.
(get_user_id): Implement using cache_get_uid_bykid.
--

This generic caching module is better than the ad-hoc code we used in
getkey.c.  More cleanup in getkey is still required but it is a
start.  There is also a small performance increase with the new cache:

With a large keyring and --list-sigs I get these numbers:

|      | before     | after      |
|------+------------+------------|
| real | 14m1.028s  | 12m16.186s |
| user |  2m18.484s |  1m36.040s |
| sys  | 11m42.420s | 10m40.044s |

Note the speedup in the user time which is due to the improved cache
algorithm.  This is obvious, because the old cache was just a long
linked list; the new cache are two hash tables.

Signed-off-by: Werner Koch <[email protected]>

1 files changed, 28 insertions, 0 deletions

diff --git a/g10/objcache.h b/g10/objcache.h
new file mode 100644
index 000000000..e92679168
--- /dev/null
+++ b/g10/objcache.h
@@ -0,0 +1,28 @@
+/* objcache.h - Caching functions for keys and user ids.
+ * Copyright (C) 2019 g10 Code GmbH
+ *
+ * This file is part of GnuPG.
+ *
+ * GnuPG is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GnuPG is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <https://www.gnu.org/licenses/>.
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#ifndef GNUPG_G10_OBJCACHE_H
+#define GNUPG_G10_OBJCACHE_H
+
+void objcache_dump_stats (void);
+void cache_put_keyblock (kbnode_t keyblock);
+char *cache_get_uid_bykid (u32 *keyid, unsigned int *r_length);
+
+#endif /*GNUPG_G10_OBJCACHE_H*/