/**************************************************
 * rtrim.c - trim trailing spaces from text files *
 *           and add / remove carriage returns    *
 *                                                *
 * usage: rtrim [+r|-r] file                      *
 *                                                *
 * +r adds carriage returns, -r removes them      *
 **************************************************/

#include <stdio.h>
#include <ctype.h>
#include <string.h>

void main(int argc, char *argv[]) {
  void usage();
  FILE *fp;
  char *cp, buf[200];
  int len = 200, i, killcr = 0, putcr = 0, file_arg = 1, end;
  if (argc < 2) {
    usage();
    return;
  }
  if (argc > 2) {
    file_arg = 2;
    if (strcmp(argv[1], "-r") == 0) {
      killcr = 1;
    }
    else if (strcmp(argv[1], "+r") == 0) putcr = 1;
  }
  if ((fp = fopen(argv[file_arg], "r")) == NULL) {
    printf("file not found %s\n", argv[1]);
    return;
  }
  while ((cp = fgets(buf, len, fp)) != NULL) {
    end = strlen(cp);
    while (1) {
      end--;
      if ((killcr == 1) && (cp[end] == '\r')) {
	cp[end] = '\0';
      }
      else if (isspace(cp[end])) {
	cp[end] = '\0';
      }
      else {
        if (putcr == 1) {
	  cp[end+1] = '\r';
	  cp[end+2] = '\0';
	}
        break;
      }
    }
    printf("%s\n", cp);
  }
  fclose(fp);
}

void usage() {
  printf("usage: rtrim [-r|+r] file\n");
}