//==========================================================================================================
// Create grammar from definitions in input file.
// Production are of the form:
// N -> A B C ...
//==========================================================================================================
void Grammar::read_grammar_file(string grammar_file) {
ifstream file = ifstream(grammar_file);
if(!file.is_open())
throw string("File " + grammar_file + " not found");
//------------------------------------------------------------------------------------------------------
// For each production line extract the symbols and add a production
//------------------------------------------------------------------------------------------------------
for(string line; getline(file, line);) {
if(trim(line, "//").empty()) continue; // Ignore comments and empty lines
vector<Symbol> symbols;
string action_name;
// If an action is specified, a number sign will serve to separate between the production and it
int split_pos = line.find_first_of('#');
extract_symbols(line.substr(0, split_pos), symbols);
if(split_pos != string::npos)
extract_action(line.substr(split_pos + 1), action_name);
productions.push_back(Production(symbols, action_name));
}
//------------------------------------------------------------------------------------------------------
// First production nonterminal considered the start symbol. If it is not START, add a production:
// START -> FIRST-NONTERMINAL
//------------------------------------------------------------------------------------------------------
if(productions[0][0] == START) {
if(productions[0].size() != 2)
throw string("Expected production for START to have just one symbol on right hand side");
if(not is_nonterminal(productions[0][1]))
throw string("Expected production for START to have a nonterminal on the right hand side");
}
else {
productions.push_front(Production({START, productions[0][0]}, ""));
}
} // read_grammar_file()
int nm(const char * filename)
{
void *data;
t_elf elf;
t_sym_list *list;
int msize;
if ((msize = map_file(&data, filename)) == -1)
return (1);
if (init_elf_data(&elf, data) == -1)
return (1);
list = extract_symbols(&elf);
list_sort(list, symcmp);
list_iter(list, print_symbol);
delete_list(list);
if (elf.ehdr->e_ident[EI_CLASS] == ELFCLASS32)
{
free(elf.ehdr);
free(elf.shtab);
}
(void)munmap(data, msize);
return (0);
}
