I had done some touchup to the A stand alone policy rule engine rule verifier and hadn't recorded why. So, I'm just going to dump the current code here. Note that I did make the changes to let the user string just be a string...

#include <stdio.h>
#include <stdarg.h>
#include <unistd.h>
#include <stdlib.h>
#include <limits.h>
#include <ctype.h>
#include <string.h>
#include <sys/types.h>
#include <errno.h>

typedef struct {
	int	uid;
	int	gid;
	int	day;
	int	hour;
	char	*user;
	char	*group;
	char	*path;
	char	*extension;
} policyAttributes_t;

int
main(int argc, char *argv[])
{
	int	i;
	int	iFlags = 0;
	int	ch;

	int	iFoundSome = 0;

	policyAttributes_t	pat;

	char	path[1024];
	char	rules[1204];

	int	rc = 0;

	char	*szJunk;

	/*
	 * Do some initialization.
	 */
	memset(&pat, '\0', sizeof(pat));

	pat.uid = 502;
	pat.gid = 100;

	/*
	 * Should pull from time of day ...
	 */
	pat.day = 1;
	pat.hour = 12;

	rules[0] = '\0';

	while ((ch = getopt(argc, argv, "?vr:p:u:g:i:h:d:e:U:G:")) != -1) {
		iFoundSome = 1;

		switch (ch) {
		case 'd' :
			pat.day = (int)strtol(optarg, &szJunk, 0);

			/*
			 * Do not worry about shorter months - buyers beware!
			 */
			if (szJunk[0] != '\0' || pat.day < 0 || pat.hour > 31) {
				fprintf(stderr, "Invalid day = %s\n", optarg);
				rc = EINVAL;
				goto cleanup;
			}

			break;
		case 'e' :
			fprintf(stdout, "The ext is %s!\n", optarg);
			break;
		case 'g' :
			pat.gid = (int)strtol(optarg, &szJunk, 0);
			if (szJunk[0] != '\0' || pat.gid < 0) {
				fprintf(stderr, "Invalid gid = %s\n", optarg);
				rc = EINVAL;
				goto cleanup;
			}

			break;
		case 'G' :
			pat.group = strdup(optarg);
			if (pat.group == NULL) {
				fprintf(stderr, "Out of memory on group name\n");
				rc = ENOMEM;
				goto cleanup;
			}

			break;
		case 'h' :
			pat.hour = (int)strtol(optarg, &szJunk, 0);
			if (szJunk[0] != '\0' || pat.hour < 0 || pat.hour > 23) {
				fprintf(stderr, "Invalid hour = %s\n", optarg);
				rc = EINVAL;
				goto cleanup;
			}

			break;
		case 'i' :
			fprintf(stdout, "in the %s,\n", optarg);
			break;
		case 'p' :
			fprintf(stdout, "with the %s!\n", optarg);
			break;
		case 'r' :
			fprintf(stdout, "The rules are in %s!\n", optarg);
			break;
		case 'u' :
			pat.uid = (int)strtol(optarg, &szJunk, 0);
			if (szJunk[0] != '\0' || pat.uid < 0) {
				fprintf(stderr, "Invalid uid = %s\n", optarg);
				rc = EINVAL;
				goto cleanup;
			}

			break;
		case 'U' :
			pat.user = strdup(optarg);
			if (pat.user == NULL) {
				fprintf(stderr, "Out of memory on user name\n");
				rc = ENOMEM;
				goto cleanup;
			}

			break;
		case 'v' :
			fprintf(stdout, "Oh, be chatty!\n");
			break;
		case '?' :
		default :
			goto usage;
		}
	}

	if (!iFoundSome) {
		goto usage;
	}

#if 0
	if (rules[0] == '\0') {
		fprintf(stderr, "Need to supply a policy ruleset file!\n");
		goto usage;
	}
#endif

	argc -= optind;
	argv += optind;
	
	goto cleanup;

usage:

	fprintf(stderr,
		"speadm explain -r rules-file [-v]"
		" [-p proposed-filename] [-u uid] [-g gid]"
		" [-U user] [-G group] [-i ip]"
		" [-h hour] [-d day]\n");
	rc = 1;

cleanup:

	if (pat.user) {
		free(pat.user);
	}

	if (pat.group) {
		free(pat.group);
	}

	return (rc);
}