s3:registry avoid updating keys which are going to be deleted in

reg_deletekey_recursive

this changes the complexity from O(n^2) to O(n) and reduces the time of
a 'net conf drop' with 10000 shares from 6min to 1.5s

Signed-off-by: Michael Adam <obnox@samba.org>

1 files changed, 34 insertions, 23 deletions

diff --git a/source3/registry/reg_api.c b/source3/registry/reg_api.c
index c66a95e406..289f77df76 100644
--- a/source3/registry/reg_api.c
+++ b/source3/registry/reg_api.c
@@ -606,41 +606,29 @@ WERROR reg_createkey(TALLOC_CTX *ctx, struct registry_key *parent,
 	return err;
 }
 
-WERROR reg_deletekey(struct registry_key *parent, const char *path)
+static WERROR reg_deletekey_internal(TALLOC_CTX *mem_ctx,
+				     struct registry_key *parent,
+				     const char *path, bool lazy)
 {
 	WERROR err;
 	char *name, *end;
-	struct registry_key *tmp_key, *key;
-	TALLOC_CTX *mem_ctx = talloc_stackframe();
-
+	struct registry_key *key;
 	name = talloc_strdup(mem_ctx, path);
 	if (name == NULL) {
 		err = WERR_NOMEM;
 		goto done;
 	}
 
-	/* check if the key has subkeys */
-	err = reg_openkey(mem_ctx, parent, name, REG_KEY_READ, &key);
-	W_ERROR_NOT_OK_GOTO_DONE(err);
-
-	err = fill_subkey_cache(key);
-	W_ERROR_NOT_OK_GOTO_DONE(err);
-
-	if (regsubkey_ctr_numkeys(key->subkeys) > 0) {
-		err = WERR_ACCESS_DENIED;
-		goto done;
-	}
-
 	/* no subkeys - proceed with delete */
 	end = strrchr(name, '\\');
 	if (end != NULL) {
 		*end = '\0';
 
 		err = reg_openkey(mem_ctx, parent, name,
-				  KEY_CREATE_SUB_KEY, &tmp_key);
+				  KEY_CREATE_SUB_KEY, &key);
 		W_ERROR_NOT_OK_GOTO_DONE(err);
 
-		parent = tmp_key;
+		parent = key;
 		name = end+1;
 	}
 
@@ -649,13 +637,36 @@ WERROR reg_deletekey(struct registry_key *parent, const char *path)
 		goto done;
 	}
 
-	err = delete_reg_subkey(parent->key, name);
+	err = delete_reg_subkey(parent->key, name, lazy);
+
+done:
+	return err;
+}
+
+WERROR reg_deletekey(struct registry_key *parent, const char *path)
+{
+	WERROR err;
+	struct registry_key *key;
+	TALLOC_CTX *mem_ctx = talloc_stackframe();
+
+	/* check if the key has subkeys */
+	err = reg_openkey(mem_ctx, parent, path, REG_KEY_READ, &key);
+	W_ERROR_NOT_OK_GOTO_DONE(err);
+
+	err = fill_subkey_cache(key);
+	W_ERROR_NOT_OK_GOTO_DONE(err);
 
+	if (regsubkey_ctr_numkeys(key->subkeys) > 0) {
+		err = WERR_ACCESS_DENIED;
+		goto done;
+	}
+	err = reg_deletekey_internal(mem_ctx, parent, path, false);
 done:
 	TALLOC_FREE(mem_ctx);
 	return err;
 }
 
+
 WERROR reg_setvalue(struct registry_key *key, const char *name,
 		    const struct registry_value *val)
 {
@@ -796,7 +807,7 @@ WERROR reg_deleteallvalues(struct registry_key *key)
  */
 static WERROR reg_deletekey_recursive_internal(struct registry_key *parent,
 					       const char *path,
-					       bool del_key)
+					       bool del_key, bool lazy)
 {
 	WERROR werr = WERR_OK;
 	struct registry_key *key;
@@ -819,13 +830,13 @@ static WERROR reg_deletekey_recursive_internal(struct registry_key *parent,
 	 */
 	for (i = regsubkey_ctr_numkeys(key->subkeys) ; i > 0; i--) {
 		subkey_name = regsubkey_ctr_specific_key(key->subkeys, i-1);
-		werr = reg_deletekey_recursive_internal(key, subkey_name, true);
+		werr = reg_deletekey_recursive_internal(key, subkey_name, true, del_key);
 		W_ERROR_NOT_OK_GOTO_DONE(werr);
 	}
 
 	if (del_key) {
 		/* now delete the actual key */
-		werr = reg_deletekey(parent, path);
+		werr = reg_deletekey_internal(mem_ctx, parent, path, lazy);
 	}
 
 done:
@@ -847,7 +858,7 @@ static WERROR reg_deletekey_recursive_trans(struct registry_key *parent,
 		return werr;
 	}
 
-	werr = reg_deletekey_recursive_internal(parent, path, del_key);
+	werr = reg_deletekey_recursive_internal(parent, path, del_key, false);
 
 	if (!W_ERROR_IS_OK(werr)) {
 		WERROR werr2;