lib/util: move memcache.[ch] to the toplevel 'samba-util' library

This is generic enough that it could be used in all code.

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Volker Lendecke <vl@samba.org>

Autobuild-User(master): Stefan Metzmacher <metze@samba.org>
Autobuild-Date(master): Fri Jul 18 15:43:33 CEST 2014 on sn-devel-104

6 files changed, 5 insertions, 426 deletions

diff --git a/source3/lib/access.c b/source3/lib/access.c
index a2de35caf4..58db722706 100644
--- a/source3/lib/access.c
+++ b/source3/lib/access.c
@@ -11,7 +11,7 @@
 */
 
 #include "includes.h"
-#include "memcache.h"
+#include "../lib/util/memcache.h"
 #include "lib/socket/interfaces.h"
 
 #define NAME_INDEX 0
diff --git a/source3/lib/gencache.c b/source3/lib/gencache.c
index 0fb1fd8280..3e67d9ebe7 100644
--- a/source3/lib/gencache.c
+++ b/source3/lib/gencache.c
@@ -25,7 +25,7 @@
 #include "system/filesys.h"
 #include "system/glob.h"
 #include "util_tdb.h"
-#include "memcache.h"
+#include "../lib/util/memcache.h"
 
 #undef  DBGC_CLASS
 #define DBGC_CLASS DBGC_TDB
diff --git a/source3/lib/id_cache.c b/source3/lib/id_cache.c
index e6e345741c..3a703ae4af 100644
--- a/source3/lib/id_cache.c
+++ b/source3/lib/id_cache.c
@@ -28,7 +28,7 @@
 #include "includes.h"
 #include "messages.h"
 #include "lib/id_cache.h"
-#include "include/memcache.h"
+#include "../lib/util/memcache.h"
 #include "idmap_cache.h"
 #include "../librpc/gen_ndr/ndr_security.h"
 #include "../libcli/security/dom_sid.h"
diff --git a/source3/lib/memcache.c b/source3/lib/memcache.c
deleted file mode 100644
index 50e59fc704..0000000000
--- a/source3/lib/memcache.c
+++ /dev/null
@@ -1,421 +0,0 @@
-/*
-   Unix SMB/CIFS implementation.
-   In-memory cache
-   Copyright (C) Volker Lendecke 2007
-
-   This program 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.
-
-   This program 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 <http://www.gnu.org/licenses/>.
-*/
-
-#include "replace.h"
-#include <talloc.h>
-#include "../lib/util/samba_util.h"
-#include "../lib/util/debug.h"
-#include "../lib/util/dlinklist.h"
-#include "../lib/util/rbtree.h"
-#include "memcache.h"
-
-static struct memcache *global_cache;
-
-struct memcache_element {
-	struct rb_node rb_node;
-	struct memcache_element *prev, *next;
-	size_t keylength, valuelength;
-	uint8_t n;		/* This is really an enum, but save memory */
-	char data[1];		/* placeholder for offsetof */
-};
-
-struct memcache {
-	struct memcache_element *mru;
-	struct rb_root tree;
-	size_t size;
-	size_t max_size;
-};
-
-static void memcache_element_parse(struct memcache_element *e,
-				   DATA_BLOB *key, DATA_BLOB *value);
-
-static bool memcache_is_talloc(enum memcache_number n)
-{
-	bool result;
-
-	switch (n) {
-	case GETPWNAM_CACHE:
-	case PDB_GETPWSID_CACHE:
-	case SINGLETON_CACHE_TALLOC:
-		result = true;
-		break;
-	default:
-		result = false;
-		break;
-	}
-
-	return result;
-}
-
-static int memcache_destructor(struct memcache *cache) {
-	struct memcache_element *e, *next;
-
-	for (e = cache->mru; e != NULL; e = next) {
-		next = e->next;
-		TALLOC_FREE(e);
-	}
-	return 0;
-}
-
-struct memcache *memcache_init(TALLOC_CTX *mem_ctx, size_t max_size)
-{
-	struct memcache *result;
-
-	result = talloc_zero(mem_ctx, struct memcache);
-	if (result == NULL) {
-		return NULL;
-	}
-	result->max_size = max_size;
-	talloc_set_destructor(result, memcache_destructor);
-	return result;
-}
-
-void memcache_set_global(struct memcache *cache)
-{
-	TALLOC_FREE(global_cache);
-	global_cache = cache;
-}
-
-static struct memcache_element *memcache_node2elem(struct rb_node *node)
-{
-	return (struct memcache_element *)
-		((char *)node - offsetof(struct memcache_element, rb_node));
-}
-
-static void memcache_element_parse(struct memcache_element *e,
-				   DATA_BLOB *key, DATA_BLOB *value)
-{
-	key->data = ((uint8_t *)e) + offsetof(struct memcache_element, data);
-	key->length = e->keylength;
-	value->data = key->data + e->keylength;
-	value->length = e->valuelength;
-}
-
-static size_t memcache_element_size(size_t key_length, size_t value_length)
-{
-	return sizeof(struct memcache_element) - 1 + key_length + value_length;
-}
-
-static int memcache_compare(struct memcache_element *e, enum memcache_number n,
-			    DATA_BLOB key)
-{
-	DATA_BLOB this_key, this_value;
-
-	if ((int)e->n < (int)n) return 1;
-	if ((int)e->n > (int)n) return -1;
-
-	if (e->keylength < key.length) return 1;
-	if (e->keylength > key.length) return -1;
-
-	memcache_element_parse(e, &this_key, &this_value);
-	return memcmp(this_key.data, key.data, key.length);
-}
-
-static struct memcache_element *memcache_find(
-	struct memcache *cache, enum memcache_number n, DATA_BLOB key)
-{
-	struct rb_node *node;
-
-	node = cache->tree.rb_node;
-
-	while (node != NULL) {
-		struct memcache_element *elem = memcache_node2elem(node);
-		int cmp;
-
-		cmp = memcache_compare(elem, n, key);
-		if (cmp == 0) {
-			return elem;
-		}
-		node = (cmp < 0) ? node->rb_left : node->rb_right;
-	}
-
-	return NULL;
-}
-
-bool memcache_lookup(struct memcache *cache, enum memcache_number n,
-		     DATA_BLOB key, DATA_BLOB *value)
-{
-	struct memcache_element *e;
-
-	if (cache == NULL) {
-		cache = global_cache;
-	}
-	if (cache == NULL) {
-		return false;
-	}
-
-	e = memcache_find(cache, n, key);
-	if (e == NULL) {
-		return false;
-	}
-
-	if (cache->size != 0) {
-		DLIST_PROMOTE(cache->mru, e);
-	}
-
-	memcache_element_parse(e, &key, value);
-	return true;
-}
-
-void *memcache_lookup_talloc(struct memcache *cache, enum memcache_number n,
-			     DATA_BLOB key)
-{
-	DATA_BLOB value;
-	void *result;
-
-	if (!memcache_lookup(cache, n, key, &value)) {
-		return NULL;
-	}
-
-	if (value.length != sizeof(result)) {
-		return NULL;
-	}
-
-	memcpy(&result, value.data, sizeof(result));
-
-	return result;
-}
-
-static void memcache_delete_element(struct memcache *cache,
-				    struct memcache_element *e)
-{
-	rb_erase(&e->rb_node, &cache->tree);
-
-	DLIST_REMOVE(cache->mru, e);
-
-	if (memcache_is_talloc(e->n)) {
-		DATA_BLOB cache_key, cache_value;
-		void *ptr;
-
-		memcache_element_parse(e, &cache_key, &cache_value);
-		SMB_ASSERT(cache_value.length == sizeof(ptr));
-		memcpy(&ptr, cache_value.data, sizeof(ptr));
-		TALLOC_FREE(ptr);
-	}
-
-	cache->size -= memcache_element_size(e->keylength, e->valuelength);
-
-	TALLOC_FREE(e);
-}
-
-static void memcache_trim(struct memcache *cache)
-{
-	if (cache->max_size == 0) {
-		return;
-	}
-
-	while ((cache->size > cache->max_size) && DLIST_TAIL(cache->mru)) {
-		memcache_delete_element(cache, DLIST_TAIL(cache->mru));
-	}
-}
-
-void memcache_delete(struct memcache *cache, enum memcache_number n,
-		     DATA_BLOB key)
-{
-	struct memcache_element *e;
-
-	if (cache == NULL) {
-		cache = global_cache;
-	}
-	if (cache == NULL) {
-		return;
-	}
-
-	e = memcache_find(cache, n, key);
-	if (e == NULL) {
-		return;
-	}
-
-	memcache_delete_element(cache, e);
-}
-
-void memcache_add(struct memcache *cache, enum memcache_number n,
-		  DATA_BLOB key, DATA_BLOB value)
-{
-	struct memcache_element *e;
-	struct rb_node **p;
-	struct rb_node *parent;
-	DATA_BLOB cache_key, cache_value;
-	size_t element_size;
-
-	if (cache == NULL) {
-		cache = global_cache;
-	}
-	if (cache == NULL) {
-		return;
-	}
-
-	if (key.length == 0) {
-		return;
-	}
-
-	e = memcache_find(cache, n, key);
-
-	if (e != NULL) {
-		memcache_element_parse(e, &cache_key, &cache_value);
-
-		if (value.length <= cache_value.length) {
-			if (memcache_is_talloc(e->n)) {
-				void *ptr;
-				SMB_ASSERT(cache_value.length == sizeof(ptr));
-				memcpy(&ptr, cache_value.data, sizeof(ptr));
-				TALLOC_FREE(ptr);
-			}
-			/*
-			 * We can reuse the existing record
-			 */
-			memcpy(cache_value.data, value.data, value.length);
-			e->valuelength = value.length;
-			return;
-		}
-
-		memcache_delete_element(cache, e);
-	}
-
-	element_size = memcache_element_size(key.length, value.length);
-
-	e = talloc_size(cache, element_size);
-	if (e == NULL) {
-		DEBUG(0, ("talloc failed\n"));
-		return;
-	}
-	talloc_set_type(e, struct memcache_element);
-
-	e->n = n;
-	e->keylength = key.length;
-	e->valuelength = value.length;
-
-	memcache_element_parse(e, &cache_key, &cache_value);
-	memcpy(cache_key.data, key.data, key.length);
-	memcpy(cache_value.data, value.data, value.length);
-
-	parent = NULL;
-	p = &cache->tree.rb_node;
-
-	while (*p) {
-		struct memcache_element *elem = memcache_node2elem(*p);
-		int cmp;
-
-		parent = (*p);
-
-		cmp = memcache_compare(elem, n, key);
-
-		p = (cmp < 0) ? &(*p)->rb_left : &(*p)->rb_right;
-	}
-
-	rb_link_node(&e->rb_node, parent, p);
-	rb_insert_color(&e->rb_node, &cache->tree);
-
-	DLIST_ADD(cache->mru, e);
-
-	cache->size += element_size;
-	memcache_trim(cache);
-}
-
-void memcache_add_talloc(struct memcache *cache, enum memcache_number n,
-			 DATA_BLOB key, void *pptr)
-{
-	void **ptr = (void **)pptr;
-	void *p;
-
-	if (cache == NULL) {
-		cache = global_cache;
-	}
-	if (cache == NULL) {
-		return;
-	}
-
-	p = talloc_move(cache, ptr);
-	memcache_add(cache, n, key, data_blob_const(&p, sizeof(p)));
-}
-
-void memcache_flush(struct memcache *cache, enum memcache_number n)
-{
-	struct rb_node *node;
-
-	if (cache == NULL) {
-		cache = global_cache;
-	}
-	if (cache == NULL) {
-		return;
-	}
-
-	/*
-	 * Find the smallest element of number n
-	 */
-
-	node = cache->tree.rb_node;
-	if (node == NULL) {
-		return;
-	}
-
-	/*
-	 * First, find *any* element of number n
-	 */
-
-	while (true) {
-		struct memcache_element *elem = memcache_node2elem(node);
-		struct rb_node *next;
-
-		if ((int)elem->n == (int)n) {
-			break;
-		}
-
-		if ((int)elem->n < (int)n) {
-			next = node->rb_right;
-		}
-		else {
-			next = node->rb_left;
-		}
-		if (next == NULL) {
-			break;
-		}
-		node = next;
-	}
-
-	/*
-	 * Then, find the leftmost element with number n
-	 */
-
-	while (true) {
-		struct rb_node *prev = rb_prev(node);
-		struct memcache_element *elem;
-
-		if (prev == NULL) {
-			break;
-		}
-		elem = memcache_node2elem(prev);
-		if ((int)elem->n != (int)n) {
-			break;
-		}
-		node = prev;
-	}
-
-	while (node != NULL) {
-		struct memcache_element *e = memcache_node2elem(node);
-		struct rb_node *next = rb_next(node);
-
-		if (e->n != n) {
-			break;
-		}
-
-		memcache_delete_element(cache, e);
-		node = next;
-	}
-}
diff --git a/source3/lib/username.c b/source3/lib/username.c
index 847aa33eab..f69d9c3bf2 100644
--- a/source3/lib/username.c
+++ b/source3/lib/username.c
@@ -21,7 +21,7 @@
 
 #include "includes.h"
 #include "system/passwd.h"
-#include "memcache.h"
+#include "../lib/util/memcache.h"
 #include "../lib/util/util_pw.h"
 
 /* internal functions */
diff --git a/source3/lib/util_sock.c b/source3/lib/util_sock.c
index c5de61a094..522f6002bc 100644
--- a/source3/lib/util_sock.c
+++ b/source3/lib/util_sock.c
@@ -21,7 +21,7 @@
 
 #include "includes.h"
 #include "system/filesys.h"
-#include "memcache.h"
+#include "../lib/util/memcache.h"
 #include "../lib/async_req/async_sock.h"
 #include "../lib/util/select.h"
 #include "lib/socket/interfaces.h"