![[tokkee]](http://tokkee.org/images/avatar.png){kind=avatar}
diff --git a/src/core/memstore_query.c b/src/core/memstore_query.c
--- /dev/null
@@ -0,0 +1,354 @@
+/*
+ * SysDB - src/core/memstore_query.c
+ * Copyright (C) 2014-2015 Sebastian 'tokkee' Harl <sh@tokkee.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "core/object.h"
+#include "core/memstore-private.h"
+#include "parser/ast.h"
+#include "utils/error.h"
+
+#include <assert.h>
+
+static sdb_memstore_matcher_t *
+node_to_matcher(sdb_ast_node_t *n);
+
+static sdb_memstore_expr_t *
+node_to_expr(sdb_ast_node_t *n)
+{
+ sdb_memstore_expr_t *left = NULL, *right = NULL;
+ sdb_memstore_expr_t *e;
+ int op;
+
+ if (! n) {
+ sdb_log(SDB_LOG_ERR, "memstore: Encountered empty AST expression node");
+ return NULL;
+ }
+
+ switch (n->type) {
+ case SDB_AST_TYPE_OPERATOR:
+ if (! SDB_AST_IS_ARITHMETIC(n)) {
+ sdb_log(SDB_LOG_ERR, "memstore: Invalid arithmetic operator of "
+ "type %s (%#x)", SDB_AST_TYPE_TO_STRING(n), n->type);
+ return NULL;
+ }
+
+ left = node_to_expr(SDB_AST_OP(n)->left);
+ if (! left)
+ return NULL;
+ right = node_to_expr(SDB_AST_OP(n)->right);
+ if (! right) {
+ sdb_object_deref(SDB_OBJ(left));
+ return NULL;
+ }
+ op = SDB_AST_OP_TO_DATA_OP(SDB_AST_OP(n)->kind);
+ e = sdb_memstore_expr_create(op, left, right);
+ break;
+
+ case SDB_AST_TYPE_CONST:
+ return sdb_memstore_expr_constvalue(&SDB_AST_CONST(n)->value);
+
+ case SDB_AST_TYPE_VALUE:
+ if (SDB_AST_VALUE(n)->type == SDB_ATTRIBUTE)
+ return sdb_memstore_expr_attrvalue(SDB_AST_VALUE(n)->name);
+ return sdb_memstore_expr_fieldvalue(SDB_AST_VALUE(n)->type);
+
+ case SDB_AST_TYPE_TYPED:
+ right = node_to_expr(SDB_AST_TYPED(n)->expr);
+ if (! right)
+ return NULL;
+ e = sdb_memstore_expr_typed(SDB_AST_TYPED(n)->type, right);
+ break;
+
+ default:
+ sdb_log(SDB_LOG_ERR, "memstore: Invalid matcher node of type %s (%#x)",
+ SDB_AST_TYPE_TO_STRING(n), n->type);
+ e = NULL;
+ }
+
+ /* expressions take a reference */
+ sdb_object_deref(SDB_OBJ(left));
+ sdb_object_deref(SDB_OBJ(right));
+ return e;
+} /* node_to_expr */
+
+static sdb_memstore_matcher_t *
+logical_to_matcher(sdb_ast_node_t *n)
+{
+ sdb_memstore_matcher_t *left = NULL, *right;
+ sdb_memstore_matcher_t *m;
+
+ if (SDB_AST_OP(n)->left) {
+ left = node_to_matcher(SDB_AST_OP(n)->left);
+ if (! left)
+ return NULL;
+ }
+ right = node_to_matcher(SDB_AST_OP(n)->right);
+ if (! right) {
+ sdb_object_deref(SDB_OBJ(left));
+ return NULL;
+ }
+
+ switch (SDB_AST_OP(n)->kind) {
+ case SDB_AST_AND:
+ m = sdb_memstore_con_matcher(left, right);
+ break;
+ case SDB_AST_OR:
+ m = sdb_memstore_dis_matcher(left, right);
+ break;
+ case SDB_AST_NOT:
+ m = sdb_memstore_inv_matcher(right);
+ break;
+
+ default:
+ m = NULL;
+ }
+
+ /* matchers take a reference */
+ sdb_object_deref(SDB_OBJ(left));
+ sdb_object_deref(SDB_OBJ(right));
+ return m;
+} /* logical_to_matcher */
+
+static sdb_memstore_matcher_t *
+cmp_to_matcher(sdb_ast_node_t *n)
+{
+ sdb_memstore_expr_t *left = NULL, *right;
+ sdb_memstore_matcher_t *m;
+
+ if (SDB_AST_OP(n)->left) {
+ left = node_to_expr(SDB_AST_OP(n)->left);
+ if (! left)
+ return NULL;
+ }
+ right = node_to_expr(SDB_AST_OP(n)->right);
+ if (! right) {
+ sdb_object_deref(SDB_OBJ(left));
+ return NULL;
+ }
+
+ switch (SDB_AST_OP(n)->kind) {
+ case SDB_AST_LT:
+ m = sdb_memstore_lt_matcher(left, right);
+ break;
+ case SDB_AST_LE:
+ m = sdb_memstore_le_matcher(left, right);
+ break;
+ case SDB_AST_EQ:
+ m = sdb_memstore_eq_matcher(left, right);
+ break;
+ case SDB_AST_NE:
+ m = sdb_memstore_ne_matcher(left, right);
+ break;
+ case SDB_AST_GE:
+ m = sdb_memstore_ge_matcher(left, right);
+ break;
+ case SDB_AST_GT:
+ m = sdb_memstore_gt_matcher(left, right);
+ break;
+ case SDB_AST_REGEX:
+ m = sdb_memstore_regex_matcher(left, right);
+ break;
+ case SDB_AST_NREGEX:
+ m = sdb_memstore_nregex_matcher(left, right);
+ break;
+ case SDB_AST_ISNULL:
+ m = sdb_memstore_isnull_matcher(right);
+ break;
+ case SDB_AST_ISTRUE:
+ m = sdb_memstore_istrue_matcher(right);
+ break;
+ case SDB_AST_ISFALSE:
+ m = sdb_memstore_isfalse_matcher(right);
+ break;
+ case SDB_AST_IN:
+ m = sdb_memstore_in_matcher(left, right);
+ break;
+
+ default:
+ sdb_log(SDB_LOG_ERR, "memstore: Invalid matcher node of type %s (%#x)",
+ SDB_AST_TYPE_TO_STRING(n), n->type);
+ m = NULL;
+ }
+
+ /* matchers take a reference */
+ sdb_object_deref(SDB_OBJ(left));
+ sdb_object_deref(SDB_OBJ(right));
+ return m;
+} /* cmp_to_matcher */
+
+static sdb_memstore_matcher_t *
+iter_to_matcher(sdb_ast_node_t *n)
+{
+ sdb_memstore_expr_t *iter;
+ sdb_memstore_matcher_t *expr, *m;
+
+ assert((SDB_AST_ITER(n)->expr->type == SDB_AST_TYPE_OPERATOR)
+ && (! SDB_AST_OP(SDB_AST_ITER(n)->expr)->left));
+
+ iter = node_to_expr(SDB_AST_ITER(n)->iter);
+ if (! iter)
+ return NULL;
+ expr = cmp_to_matcher(SDB_AST_ITER(n)->expr);
+ if (! expr) {
+ sdb_object_deref(SDB_OBJ(iter));
+ return NULL;
+ }
+
+ switch (SDB_AST_ITER(n)->kind) {
+ case SDB_AST_ALL:
+ m = sdb_memstore_all_matcher(iter, expr);
+ break;
+ case SDB_AST_ANY:
+ m = sdb_memstore_any_matcher(iter, expr);
+ break;
+
+ default:
+ sdb_log(SDB_LOG_ERR, "memstore: Invalid iterator node of type %s (%#x)",
+ SDB_AST_OP_TO_STRING(SDB_AST_ITER(n)->kind), SDB_AST_ITER(n)->kind);
+ m = NULL;
+ }
+
+ /* matchers take a reference */
+ sdb_object_deref(SDB_OBJ(iter));
+ sdb_object_deref(SDB_OBJ(expr));
+ return m;
+} /* iter_to_matcher */
+
+static sdb_memstore_matcher_t *
+node_to_matcher(sdb_ast_node_t *n)
+{
+ int kind;
+
+ if (! n) {
+ sdb_log(SDB_LOG_ERR, "memstore: Encountered empty AST matcher node");
+ return NULL;
+ }
+
+ switch (n->type) {
+ case SDB_AST_TYPE_OPERATOR:
+ if (! SDB_AST_IS_LOGICAL(n)) {
+ sdb_log(SDB_LOG_ERR, "memstore: Invalid logical operator of "
+ "type %s (%#x)", SDB_AST_TYPE_TO_STRING(n), n->type);
+ return NULL;
+ }
+
+ kind = SDB_AST_OP(n)->kind;
+ if ((kind == SDB_AST_AND) || (kind == SDB_AST_OR) || (kind == SDB_AST_NOT))
+ return logical_to_matcher(n);
+ else
+ return cmp_to_matcher(n);
+
+ case SDB_AST_TYPE_ITERATOR:
+ return iter_to_matcher(n);
+ }
+
+ sdb_log(SDB_LOG_ERR, "memstore: Invalid matcher node of type %s (%#x)",
+ SDB_AST_TYPE_TO_STRING(n), n->type);
+ return NULL;
+} /* node_to_matcher */
+
+/*
+ * query type
+ */
+
+static int
+query_init(sdb_object_t *obj, va_list ap)
+{
+ sdb_ast_node_t *ast = va_arg(ap, sdb_ast_node_t *);
+ sdb_ast_node_t *matcher = NULL, *filter = NULL;
+
+ QUERY(obj)->ast = ast;
+ sdb_object_ref(SDB_OBJ(ast));
+
+ switch (ast->type) {
+ case SDB_AST_TYPE_FETCH:
+ filter = SDB_AST_FETCH(ast)->filter;
+ break;
+ case SDB_AST_TYPE_LIST:
+ filter = SDB_AST_LIST(ast)->filter;
+ break;
+ case SDB_AST_TYPE_LOOKUP:
+ matcher = SDB_AST_LOOKUP(ast)->matcher;
+ filter = SDB_AST_LOOKUP(ast)->filter;
+ break;
+ case SDB_AST_TYPE_STORE:
+ case SDB_AST_TYPE_TIMESERIES:
+ /* nothing to do */
+ break;
+
+ default:
+ sdb_log(SDB_LOG_ERR, "memstore: Invalid top-level AST node "
+ "of type %#x", ast->type);
+ return -1;
+ }
+
+ if (matcher) {
+ QUERY(obj)->matcher = node_to_matcher(matcher);
+ if (! QUERY(obj)->matcher)
+ return -1;
+ }
+ if (filter) {
+ QUERY(obj)->filter = node_to_matcher(filter);
+ if (! QUERY(obj)->filter)
+ return -1;
+ }
+
+ return 0;
+} /* query_init */
+
+static void
+query_destroy(sdb_object_t *obj)
+{
+ sdb_object_deref(SDB_OBJ(QUERY(obj)->ast));
+ sdb_object_deref(SDB_OBJ(QUERY(obj)->matcher));
+ sdb_object_deref(SDB_OBJ(QUERY(obj)->filter));
+} /* query_destroy */
+
+static sdb_type_t query_type = {
+ /* size = */ sizeof(sdb_memstore_query_t),
+ /* init = */ query_init,
+ /* destroy = */ query_destroy,
+};
+
+/*
+ * public API
+ */
+
+sdb_memstore_query_t *
+sdb_memstore_query_prepare(sdb_ast_node_t *ast)
+{
+ if (! ast)
+ return NULL;
+ return QUERY(sdb_object_create(SDB_AST_TYPE_TO_STRING(ast), query_type, ast));
+} /* sdb_memstore_query_prepare */
+
+sdb_memstore_matcher_t *
+sdb_memstore_query_prepare_matcher(sdb_ast_node_t *ast)
+{
+ return node_to_matcher(ast);
+} /* sdb_memstore_query_prepare_matcher */
+
+/* vim: set tw=78 sw=4 ts=4 noexpandtab : */