/* dumpwtmp.c   by Michael Thorpe   2008-12-12 */

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

int main(int argc,char **argv) {
	FILE *f;
	struct utmp ut;
	int i;
	unsigned char *ctmp;
	unsigned short *stmp;

	f=fopen((2==argc)?argv[1]:"/var/log/wtmp","rb");
	if(!f) {
		perror("open");
		return(1);
	}
	while(1==fread((void *)&ut,sizeof(ut),1,f)) {
		switch(ut.ut_type) {
		case UT_UNKNOWN: fputs("UT_UNKNOWN",stdout); break;
		case RUN_LVL: fputs("RUN_LVL",stdout); break;
		case BOOT_TIME: fputs("BOOT_TIME",stdout); break;
		case NEW_TIME: fputs("NEW_TIME",stdout); break;
		case OLD_TIME: fputs("OLD_TIME",stdout); break;
		case INIT_PROCESS: fputs("INIT_PROCESS",stdout); break;
		case LOGIN_PROCESS: fputs("LOGIN_PROCESS",stdout); break;
		case USER_PROCESS: fputs("login",stdout); break;
		case DEAD_PROCESS: fputs("logout",stdout); break;
		case ACCOUNTING: fputs("ACCOUNTING",stdout); break;
		default: printf("%d",ut.ut_type); break;
		}
		printf("\t%u\t",ut.ut_pid);
		for(i=0;i<UT_LINESIZE && isprint(ut.ut_line[i]);i++)
			putchar(ut.ut_line[i]);
/* char ut_id[4]; */
		putchar('\t');
		for(i=0;i<UT_NAMESIZE && isprint(ut.ut_user[i]);i++)
			putchar(ut.ut_user[i]);
		putchar('\t');
		for(i=0;i<UT_HOSTSIZE && isprint(ut.ut_host[i]);i++)
			putchar(ut.ut_host[i]);
/* struct exit_status ut_exit; */
/* int32_t ut_session; */
		printf("\t%lu.%06lu\t",(unsigned long)ut.ut_tv.tv_sec,(unsigned long)ut.ut_tv.tv_usec);
		if(ut.ut_addr_v6[1] || ut.ut_addr_v6[2] || ut.ut_addr_v6[3]) {
			stmp=(unsigned short *)ut.ut_addr_v6;
			for(i=0;i<8;i++) {
				if(i)
					putchar(':');
				printf("%4.4X",stmp[i]);
			}
		} else if(ut.ut_addr_v6[0]) {
			ctmp=(unsigned char *)ut.ut_addr_v6;
			for(i=0;i<4;i++) {
				if(i)
					putchar('.');
				printf("%u",ctmp[i]);
			}
		}
/* char __unused[20]; */
		putchar('\n');
	}
	if(fclose(f)) {
		perror("close");
		return(1);
	}
	return(0);
}