hammer/examples/dns_common.c

#include "../src/hammer.h"
#include "dns_common.h"

#define false 0
#define true 1

/**
 * A label can't be more than 63 characters.
 */
bool validate_label(HParseResult *p) {
  if (TT_SEQUENCE != p->ast->token_type)
    return false;
  return (64 > p->ast->seq->used);
}


const HParser* init_domain() {
  static const HParser *ret = NULL;
  if (ret)
    return ret;

  H_RULE (letter,    h_choice(h_ch_range('a','z'), h_ch_range('A','Z'), NULL));
  H_RULE (let_dig,   h_choice(letter, h_ch_range('0','9'), NULL));
  H_RULE (ldh_str,   h_many1(h_choice(let_dig, h_ch('-'), NULL)));
  H_RULE (label,     h_attr_bool(h_sequence(letter,
					    h_optional(h_sequence(h_optional(ldh_str),
								  let_dig,
								  NULL)),
					    NULL),
			         validate_label));
  H_RULE (subdomain, h_sepBy1(label, h_ch('.')));
  H_RULE (domain,    h_choice(subdomain, h_ch(' '), NULL));

  ret = domain;
  return ret;
}

const HParser* init_character_string() {
  static const HParser *cstr = NULL;
  if (cstr)
    return cstr;

  cstr = h_length_value(h_uint8(), h_uint8());

  return cstr;
}