schema parsers CHANGE check for prefix duplicity
diff --git a/src/tree_schema_internal.h b/src/tree_schema_internal.h
new file mode 100644
index 0000000..dda9593
--- /dev/null
+++ b/src/tree_schema_internal.h
@@ -0,0 +1,37 @@
+/**
+ * @file tree_schema_internal.h
+ * @author Radek Krejci <rkrejci@cesnet.cz>
+ * @brief internal functions for YANG schema trees.
+ *
+ * Copyright (c) 2015 - 2018 CESNET, z.s.p.o.
+ *
+ * This source code is licensed under BSD 3-Clause License (the "License").
+ * You may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * https://opensource.org/licenses/BSD-3-Clause
+ */
+
+#ifndef LY_TREE_SCHEMA_INTERNAL_H_
+#define LY_TREE_SCHEMA_INTERNAL_H_
+
+/**
+ * @brief internal context for schema parsers
+ */
+struct ly_parser_ctx {
+ struct ly_ctx *ctx;
+ uint64_t line; /* line number */
+ uint64_t indent; /* current position on the line for YANG indentation */
+};
+
+/**
+ * @brief Check the currently present prefixes in the module for collision with the new one.
+ *
+ * @param[in] ctx yang parser context.
+ * @param[in] module Schema tree to check.
+ * @param[in] value Newly added prefix value (including its location to distinguish collision with itself).
+ * @return LY_EEXIST when prefix is already used in the module, LY_SUCCESS otherwise
+ */
+LY_ERR lysp_check_prefix(struct ly_parser_ctx *ctx, struct lysp_module *module, const char **value);
+
+#endif /* LY_TREE_SCHEMA_INTERNAL_H_ */