Recursive descent parser for paren

#include "paren_recur.h"

bool paren(void) {
  int c;
  for (c = getchar(); c != EOF; c = getchar()) {
    if ((unsigned char) c == '(') {
      if (paren()) continue;
      printf(") not appear\n");
      return false;
    }
    if ((unsigned char) c == '{') {
      if (brace()) continue;
      printf("} not appear\n");
      return false;
    }
    if ((unsigned char) c == ')') return true;
    if ((unsigned char) c == '}') {
      printf("(} mismatch\n");
      return false;
    }
  }
  return false;
}

bool brace(void) {
  int c;
  for (c = getchar(); c != EOF; c = getchar()) {
    if ((unsigned char) c == '(') {
      if (paren()) continue;
      printf(") not appear\n");
      return false;
    }
    if ((unsigned char) c == '{') {
      if (brace()) continue;
      printf("} not appear\n");
      return false;
    }
    if ((unsigned char) c == ')') {
      printf("{) mismatch\n");
      return false;
    }
    if ((unsigned char) c == '}') return true;

  }
  return false;
}

int main(int ac, char **av) {
  int c;
  for (c = getchar(); c != EOF; c = getchar()) {
    if ((unsigned char) c == '(') {
      if (paren()) continue;
      printf("() unmatch\n");
      return EXIT_FAILURE;
    }
    if ((unsigned char) c == '{') {
      if (brace()) continue;
      printf("{} unmatch\n");
      return EXIT_FAILURE;
    }
  }
  printf("(){} match\n");
  return EXIT_SUCCESS;
}