gazprea-fuzzer-python/ast_parser/ast_parser.py

import os
import shutil
import xml.etree.ElementTree as ET


def to_gazprea_type(ty: str):
    if ty == "int":
        return "integer"
    elif ty == "bool":
        return "boolean"
    elif ty == "string":
        return "string"
    elif ty == 'void':
        return 'void'
    else:
        raise Exception("Unknown type: " + ty)


class AstParser:
    def __init__(self, input: str or ET.Element, from_xml: bool = False):
        if from_xml:
            self.xml = input
            self.input = None
        else:
            self.input = input
            self.xml = None

        self.indentation = 0


    def parse(self):
        if os.path.isdir("/home/stormblessed/Code/gazprea_fuzzer_v0.2/ast_parser/test/.tmp"):
            os.system("rm -rf /home/stormblessed/Code/gazprea_fuzzer_v0.2/ast_parser/test/.tmp")
            os.mkdir("/home/stormblessed/Code/gazprea_fuzzer_v0.2/ast_parser/test/.tmp")
        else:
            os.mkdir("/home/stormblessed/Code/gazprea_fuzzer_v0.2/ast_parser/test/.tmp")
        with open("/home/stormblessed/Code/gazprea_fuzzer_v0.2/ast_parser/test/.tmp/input.in", "x") as f:
            f.write(self.input)
        os.system("/home/stormblessed/.local/bin/gazc "
                  "/home/stormblessed/Code/gazprea_fuzzer_v0.2/ast_parser/test/.tmp/input.in "
                  "/home/stormblessed/Code/gazprea_fuzzer_v0.2/ast_parser/test/.tmp/output.out "
                  "/home/stormblessed/Code/gazprea_fuzzer_v0.2/ast_parser/test/.tmp/xml.xml")
        self.xml = ET.parse(".tmp/xml.xml")

    def unparse(self):
        """
        @brief unparses the xml into valid gazprea code

        :return: a string of valid gazprea code
        """
        self.input = ""
        for node in self.xml:
            self._unparse_node(node)

    def _unparse_node(self, node):
        if node.tag not in ["variable", "rhs", "lhs", "literal", "operator"]:
            self.input += " " * self.indentation

        if node.tag == "block":
            self._block_unparse(node)
        elif node.tag == "declaration":
            self._declaration_unparse(node)
        elif node.tag == "return":
            self._return_unparse(node)
        elif node.tag == "operator":
            self._operator_unparse(node)
        elif node.tag == "stream":
            self._stream_unparse(node)
        elif node.tag == "literal":
            self._literal_unparse(node)
        elif node.tag == "procedure" or node.tag == "function":
            self._routine_unparse(node)
        elif node.tag == "variable":
            self._variable_unparse(node)
        elif node.tag == "rhs" or node.tag == "lhs":
            self._xhs_unparse(node)
        elif node.tag == "literal":
            self._literal_unparse(node)
        else:
            raise Exception("Unknown tag: " + node.tag)

    def _block_unparse(self, node):
        self.input += "{\n"
        self.indentation += 4
        for child in node:
            self._unparse_node(child)
        self.indentation -= 4
        self.input += "}\n\n"

    def _declaration_unparse(self, node):
        variable = node.find("variable")
        rhs = node.find("rhs")
        self._variable_unparse(variable, True)
        self.input += "="
        self._unparse_node(rhs)
        self.input += ";\n"

    def _variable_unparse(self, node, is_declaration = False):
        if is_declaration:
            mut = node.get("mut")
            type = to_gazprea_type(node.get("type"))
            name = node.get("name")

            self.input += "{} {} {} ".format(mut, type, name)
        else:
            self.input += " {} ".format(node.get("name"))

    def _stream_unparse(self, node):
        for child in node:
            self._unparse_node(child)

        self.input += "-> {};\n".format(node.get("type"))

    def _literal_unparse(self, node):
        self.input += " {} ".format(node.get("value"))

    def _xhs_unparse(self, node):
        for child in node:
            self._unparse_node(child)

    def _operator_unparse(self, node):
        self._xhs_unparse(node.find("lhs"))
        self.input += "{}".format(node.get("op"))
        self._xhs_unparse(node.find("rhs"))

    def _return_unparse(self, node):
        self.input += "return"
        for child in node:
            self._unparse_node(child)
        self.input += ";\n"

    def _routine_unparse(self, node):
        return_type = ""
        if node.get("return_type") != "":
            return_type = "returns " + to_gazprea_type(node.get("return_type"))

        self.input += "{} {}{} {} ".format(
            node.tag,
            node.get("name"),
            node.get("args"),
            return_type,
        )

        for child in node:
            self._unparse_node(child)

        # self.input += "}\n\n" #blocks are already there


if __name__ == '__main__':
        input = """
            function art() returns integer {
                return 3;
            }
            procedure main() returns integer {
                integer b = art();
                integer a = 1;
                a * 42 -> std_output;
                return 0;
            }
        """

        parser = AstParser(input)
        parser.parse()