/* bpbcounts.c - character code frequencies.
 * filter counting the occurrences of opening and closing brace, parenthesis,
 * and bracket characters.  cf BE, 250707 NG.
 * usage:  bpbcounts < file.{inc,pov}
 */

#define _GNU_SOURCE

#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <unistd.h>

#define MAXV  256


int main(void) {
  int c;
  unsigned long v[MAXV] = {0L};  /* value counts array */
  unsigned long nv = 0L;         /* total */

  /* drop privileges */
  setregid(getgid(), getgid());

  /* while there are characters on input stream */
  while (EOF != (c = fgetc(stdin))) {
    ++v[(size_t)c];
    ++nv;
  }

  /* output counts */
  if (0 < nv) {
    printf("counts of paired characters:\n");
    printf("    parentheses '%c' %3lu  '%c' %3lu\n", 40, v[40], 41, v[41]);
    printf(" angle brackets '%c' %3lu  '%c' %3lu\n", 60, v[60], 62, v[62]);
    printf("square brackets '%c' %3lu  '%c' %3lu\n", 91, v[91], 93, v[93]);
    printf("         braces '%c' %3lu  '%c' %3lu\n", 123, v[123], 125, v[125]);
  }

  exit(EXIT_SUCCESS);
}