blog-static/code/compiler/13/parse_driver.hpp

#pragma once
#include <string>
#include <fstream>
#include <sstream>
#include "definition.hpp"
#include "location.hh"
#include "parser.hpp"

struct parse_driver;

void scanner_init(parse_driver* d, yyscan_t* scanner);
void scanner_destroy(yyscan_t* scanner);

struct parse_driver {
    std::string file_name;
    std::ifstream file_stream;
    std::ostringstream string_stream;

    yy::location location;
    size_t file_offset;

    std::vector<size_t> line_offsets;
    definition_group global_defs;
    std::string read_file;

    parse_driver(const std::string& file)
        : file_name(file), file_offset(0) {}

    void run_parse() {
        file_stream.open(file_name);
        if(!file_stream.good()) throw 0;
        line_offsets.push_back(0);
        yyscan_t scanner;
        scanner_init(this, &scanner);
        yy::parser parser(scanner, *this);
        parser();
        scanner_destroy(&scanner);
        read_file = string_stream.str();
    }

    int get() {
        int new_char = file_stream.get();
        if(new_char == EOF) return EOF;
        file_offset++;
        if(new_char == '\n') line_offsets.push_back(file_offset);
        string_stream.put(new_char);
        return new_char;
    }

    size_t get_index(int line, int column) {
        assert(line > 0);
        assert(line <= line_offsets.size());
        size_t file_offset = line_offsets[line-1];
        file_offset += column - 1;
        return file_offset;
    }

    size_t get_line_end(int line) {
        if(line > line_offsets.size()) return read_file.size();
        return get_index(line+1, 1);
    }
};

#define YY_DECL yy::parser::symbol_type yylex(yyscan_t yyscanner, parse_driver& drv)

YY_DECL;