X-Git-Url: https://git.tokkee.org/?p=sysdb.git;a=blobdiff_plain;f=src%2Fcore%2Fstore_expr.c;h=6e39305a89ecd18718ad7984a4e7cc85f407728d;hp=4e8bae7cad7c980941145938597be86e1bb770f3;hb=da52b4da948c741d20c7a3995ce5d133af377def;hpb=22aa3b95ef9e01872eb7bd645c8dfea723b9c9d2

diff --git a/src/core/store_expr.c b/src/core/store_expr.c
index 4e8bae7..6e39305 100644
--- a/src/core/store_expr.c
+++ b/src/core/store_expr.c
@@ -46,29 +46,21 @@
  * private data types
  */
 
-/*
- * expression types:
- */
-enum {
-	ATTR_VALUE  = -2, /* attr name stored in data.data.string */
-	FIELD_VALUE = -1, /* field type stored in data.data.integer */
-	/*  0: const value (stored in data) */
-	/* >0: operator id */
-};
-
-struct sdb_store_expr {
-	sdb_object_t super;
+/* iterate through either a list of child nodes or arrays */
+struct sdb_store_expr_iter {
+	sdb_store_obj_t *obj;
+	sdb_store_expr_t *expr;
 
-	int type; /* see above */
+	sdb_avltree_iter_t *tree;
 
-	sdb_store_expr_t *left;
-	sdb_store_expr_t *right;
+	sdb_data_t array;
+	size_t array_idx;
 
-	sdb_data_t data;
+	sdb_store_matcher_t *filter;
 };
 
 /*
- * private data types
+ * private types
  */
 
 static int
@@ -84,6 +76,8 @@ expr_init(sdb_object_t *obj, va_list ap)
 	if (type <= 0) {
 		if (! value)
 			return -1;
+		if ((type == TYPED_EXPR) && (! left))
+			return -1;
 	} else {
 		if (value)
 			return -1;
@@ -100,6 +94,9 @@ expr_init(sdb_object_t *obj, va_list ap)
 	expr->type  = type;
 	expr->left  = left;
 	expr->right = right;
+
+	/* unknown for now */
+	expr->data_type = -1;
 	return 0;
 } /* expr_init */
 
@@ -128,29 +125,54 @@ sdb_store_expr_t *
 sdb_store_expr_create(int op, sdb_store_expr_t *left, sdb_store_expr_t *right)
 {
 	sdb_data_t value = SDB_DATA_INIT;
+	sdb_store_expr_t *e;
 
 	if ((op < 0) || (SDB_DATA_CONCAT < op) || (! left) || (! right))
 		return NULL;
 
-	if (left->type || right->type)
-		return SDB_STORE_EXPR(sdb_object_create("store-expr", expr_type,
+	if (left->type || right->type) {
+		e = SDB_STORE_EXPR(sdb_object_create("store-expr", expr_type,
 					op, left, right, NULL));
+		e->data_type = sdb_data_expr_type(op, left->type, right->type);
+		return e;
+	}
 	/* else: both expressions are constant values; evaluate now */
 
 	if (sdb_data_expr_eval(op, &left->data, &right->data, &value))
 		return NULL;
-	return SDB_STORE_EXPR(sdb_object_create("store-constvalue", expr_type,
+	e = SDB_STORE_EXPR(sdb_object_create("store-constvalue", expr_type,
 				0, NULL, NULL, &value));
+	e->data_type = value.type;
+	return e;
 } /* sdb_store_expr_create */
 
+sdb_store_expr_t *
+sdb_store_expr_typed(int typ, sdb_store_expr_t *expr)
+{
+	sdb_data_t value = { SDB_TYPE_INTEGER, { .integer = typ } };
+	sdb_store_expr_t *e;
+
+	if ((typ < SDB_HOST) || (SDB_ATTRIBUTE < typ))
+		return NULL;
+
+	e = SDB_STORE_EXPR(sdb_object_create("store-typedexpr", expr_type,
+				TYPED_EXPR, expr, NULL, &value));
+	e->data_type = expr->data_type;
+	return e;
+} /* sdb_store_expr_typed */
+
 sdb_store_expr_t *
 sdb_store_expr_fieldvalue(int field)
 {
 	sdb_data_t value = { SDB_TYPE_INTEGER, { .integer = field } };
-	if ((field < 0) || (SDB_FIELD_BACKEND < field))
+	sdb_store_expr_t *e;
+
+	if ((field < SDB_FIELD_NAME) || (SDB_FIELD_VALUE < field))
 		return NULL;
-	return SDB_STORE_EXPR(sdb_object_create("store-fieldvalue", expr_type,
+	e = SDB_STORE_EXPR(sdb_object_create("store-fieldvalue", expr_type,
 				FIELD_VALUE, NULL, NULL, &value));
+	e->data_type = SDB_FIELD_TYPE(field);
+	return e;
 } /* sdb_store_expr_fieldvalue */
 
 sdb_store_expr_t *
@@ -167,6 +189,7 @@ sdb_store_expr_attrvalue(const char *name)
 				ATTR_VALUE, NULL, NULL, &value));
 	if (! expr)
 		free(value.data.string);
+	expr->data_type = -1;
 	return expr;
 } /* sdb_store_expr_attrvalue */
 
@@ -174,10 +197,14 @@ sdb_store_expr_t *
 sdb_store_expr_constvalue(const sdb_data_t *value)
 {
 	sdb_data_t data = SDB_DATA_INIT;
+	sdb_store_expr_t *e;
+
 	if (sdb_data_copy(&data, value))
 		return NULL;
-	return SDB_STORE_EXPR(sdb_object_create("store-constvalue", expr_type,
+	e = SDB_STORE_EXPR(sdb_object_create("store-constvalue", expr_type,
 				0, NULL, NULL, &data));
+	e->data_type = data.type;
+	return e;
 } /* sdb_store_expr_constvalue */
 
 int
@@ -197,8 +224,28 @@ sdb_store_expr_eval(sdb_store_expr_t *expr, sdb_store_obj_t *obj,
 		return sdb_data_copy(res, &expr->data);
 	else if (expr->type == FIELD_VALUE)
 		return sdb_store_get_field(obj, (int)expr->data.data.integer, res);
-	else if (expr->type == ATTR_VALUE)
-		return sdb_store_get_attr(obj, expr->data.data.string, res, filter);
+	else if (expr->type == ATTR_VALUE) {
+		status = sdb_store_get_attr(obj, expr->data.data.string, res, filter);
+		if ((status < 0) && obj) {
+			/* attribute does not exist => NULL */
+			status = 0;
+			res->type = SDB_TYPE_STRING;
+			res->data.string = NULL;
+		}
+		return status;
+	}
+	else if (expr->type == TYPED_EXPR) {
+		int typ = (int)expr->data.data.integer;
+		if (typ != obj->type) {
+			/* we support self-references and { service, metric } -> host */
+			if ((typ != SDB_HOST)
+					|| ((obj->type != SDB_SERVICE)
+						&& (obj->type != SDB_METRIC)))
+				return -1;
+			obj = obj->parent;
+		}
+		return sdb_store_expr_eval(expr->left, obj, res, filter);
+	}
 
 	if (sdb_store_expr_eval(expr->left, obj, &v1, filter))
 		return -1;
@@ -214,5 +261,206 @@ sdb_store_expr_eval(sdb_store_expr_t *expr, sdb_store_obj_t *obj,
 	return status;
 } /* sdb_store_expr_eval */
 
+bool
+sdb_store_expr_iterable(sdb_store_expr_t *expr, int context)
+{
+	if (expr->type == TYPED_EXPR) {
+		if ((context != SDB_HOST) && (context != SDB_SERVICE)
+				&& (context != SDB_METRIC))
+			return 0;
+		if (context == expr->data.data.integer)
+			return 0;
+		if ((expr->data.data.integer != SDB_SERVICE)
+				&& (expr->data.data.integer != SDB_METRIC)
+				&& (expr->data.data.integer != SDB_ATTRIBUTE))
+			return 0;
+		if ((context == SDB_SERVICE)
+				&& (expr->data.data.integer == SDB_METRIC))
+			return 0;
+		else if ((context == SDB_METRIC)
+				&& (expr->data.data.integer == SDB_SERVICE))
+			return 0;
+		return 1;
+	}
+	else if (expr->type == FIELD_VALUE) {
+		if ((context != SDB_HOST) && (context != SDB_SERVICE)
+				&& (context != SDB_METRIC) && (context != SDB_ATTRIBUTE))
+			return 0;
+		if (expr->data.data.integer == SDB_FIELD_BACKEND)
+			return 1;
+		else if (expr->data.data.integer == SDB_FIELD_VALUE)
+			/* we don't current support this just like when using
+			 * the attribute[<name>] syntax */
+			return 0;
+	}
+	else if (! expr->type) {
+		return !!(expr->data.type & SDB_TYPE_ARRAY);
+	}
+	return 0;
+} /* sdb_store_expr_iterable */
+
+sdb_store_expr_iter_t *
+sdb_store_expr_iter(sdb_store_expr_t *expr, sdb_store_obj_t *obj,
+		sdb_store_matcher_t *filter)
+{
+	sdb_store_expr_iter_t *iter;
+	sdb_avltree_iter_t *tree = NULL;
+	sdb_data_t array = SDB_DATA_INIT;
+
+	if (! expr)
+		return NULL;
+
+	if (expr->type == TYPED_EXPR) {
+		if (! obj)
+			return NULL;
+		if (obj->type == SDB_HOST) {
+			if (expr->data.data.integer == SDB_SERVICE)
+				tree = sdb_avltree_get_iter(HOST(obj)->services);
+			else if (expr->data.data.integer == SDB_METRIC)
+				tree = sdb_avltree_get_iter(HOST(obj)->metrics);
+			else if (expr->data.data.integer == SDB_ATTRIBUTE)
+				tree = sdb_avltree_get_iter(HOST(obj)->attributes);
+		}
+		else if (obj->type == SDB_SERVICE) {
+			if (expr->data.data.integer == SDB_ATTRIBUTE)
+				tree = sdb_avltree_get_iter(SVC(obj)->attributes);
+		}
+		else if (obj->type == SDB_METRIC) {
+			if (expr->data.data.integer == SDB_ATTRIBUTE)
+				tree = sdb_avltree_get_iter(METRIC(obj)->attributes);
+		}
+	}
+	else if (expr->type == FIELD_VALUE) {
+		if (! obj)
+			return NULL;
+		if (expr->data.data.integer == SDB_FIELD_BACKEND) {
+			/* while scanning the store, we hold a read lock, so it's safe to
+			 * access the data without copying */
+			array.type = SDB_TYPE_ARRAY | SDB_TYPE_STRING;
+			array.data.array.length = obj->backends_num;
+			array.data.array.values = obj->backends;
+		}
+	}
+	else if (! expr->type) {
+		if (expr->data.type & SDB_TYPE_ARRAY)
+			array = expr->data;
+	}
+	else
+		return NULL;
+
+	if ((! tree) && (array.type == SDB_TYPE_NULL))
+		return NULL;
+
+	iter = calloc(1, sizeof(*iter));
+	if (! iter)
+		return NULL;
+
+	sdb_object_ref(SDB_OBJ(obj));
+	sdb_object_ref(SDB_OBJ(expr));
+	sdb_object_ref(SDB_OBJ(filter));
+
+	iter->obj = obj;
+	iter->expr = expr;
+	iter->tree = tree;
+	iter->array = array;
+	iter->filter = filter;
+	return iter;
+} /* sdb_store_expr_iter */
+
+void
+sdb_store_expr_iter_destroy(sdb_store_expr_iter_t *iter)
+{
+	sdb_data_t null = SDB_DATA_INIT;
+
+	if (! iter)
+		return;
+
+	if (iter->tree)
+		sdb_avltree_iter_destroy(iter->tree);
+	iter->tree = NULL;
+
+	iter->array = null;
+	iter->array_idx = 0;
+
+	sdb_object_deref(SDB_OBJ(iter->obj));
+	sdb_object_deref(SDB_OBJ(iter->expr));
+	sdb_object_deref(SDB_OBJ(iter->filter));
+	free(iter);
+} /* sdb_store_expr_iter_destroy */
+
+bool
+sdb_store_expr_iter_has_next(sdb_store_expr_iter_t *iter)
+{
+	if (! iter)
+		return 0;
+
+	if (iter->tree) {
+		/* this function may be called before get_next,
+		 * so we'll have to apply filters here as well */
+		if (iter->filter) {
+			sdb_store_obj_t *child;
+			while ((child = STORE_OBJ(sdb_avltree_iter_peek_next(iter->tree)))) {
+				if (sdb_store_matcher_matches(iter->filter, child, NULL))
+					break;
+				(void)sdb_avltree_iter_get_next(iter->tree);
+			}
+		}
+
+		return sdb_avltree_iter_has_next(iter->tree);
+	}
+
+	return iter->array_idx < iter->array.data.array.length;
+} /* sdb_store_expr_iter_has_next */
+
+sdb_data_t
+sdb_store_expr_iter_get_next(sdb_store_expr_iter_t *iter)
+{
+	sdb_data_t null = SDB_DATA_INIT;
+	sdb_data_t ret = SDB_DATA_INIT;
+	sdb_data_t tmp = SDB_DATA_INIT;
+
+	if (! iter)
+		return null;
+
+	if (iter->tree) {
+		sdb_store_obj_t *child;
+
+		while (42) {
+			child = STORE_OBJ(sdb_avltree_iter_get_next(iter->tree));
+			if (! child)
+				break;
+			if (iter->filter
+					&& (! sdb_store_matcher_matches(iter->filter, child, NULL)))
+				continue;
+
+			if (sdb_store_expr_eval(iter->expr, child, &ret, iter->filter))
+				return null;
+			break;
+		}
+
+		/* Skip over any filtered objects */
+		if (iter->filter) {
+			while ((child = STORE_OBJ(sdb_avltree_iter_peek_next(iter->tree)))) {
+				if (sdb_store_matcher_matches(iter->filter, child, NULL))
+					break;
+				(void)sdb_avltree_iter_get_next(iter->tree);
+			}
+		}
+
+		return ret;
+	}
+
+	if (iter->array_idx >= iter->array.data.array.length)
+		return null;
+
+	++iter->array_idx;
+	if (sdb_data_array_get(&iter->array, iter->array_idx - 1, &ret))
+		return null;
+	if (sdb_data_copy(&tmp, &ret))
+		return null;
+	ret = tmp;
+	return ret;
+} /* sdb_store_expr_iter_get_next */
+
 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */