uclibc-ng/libutil/logwtmp.c

/* vi: set sw=4 ts=4: */
/*
 * wtmp support rubbish (i.e. complete crap)
 * Copyright (C) 2000-2006 by Erik Andersen <andersen@uclibc.org>
 * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
 */

#include <string.h>
#include <sys/time.h>
#include <time.h>
#include <unistd.h>
#include <utmp.h>
#include <fcntl.h>
#include <sys/file.h>

void logwtmp(const char *line, const char *name, const char *host)
{
    struct utmp lutmp;
    memset(&lutmp, 0, sizeof(lutmp));

    lutmp.ut_type = (name && *name) ? USER_PROCESS : DEAD_PROCESS;
    lutmp.ut_pid = getpid();
    strncpy(lutmp.ut_line, line, sizeof(lutmp.ut_line)-1);
    strncpy(lutmp.ut_name, name, sizeof(lutmp.ut_name)-1);
    strncpy(lutmp.ut_host, host, sizeof(lutmp.ut_host)-1);
#if !defined __WORDSIZE_COMPAT32 || __WORDSIZE_COMPAT32 == 0
    gettimeofday(&lutmp.ut_tv, NULL);
#else
    {
      struct timeval tv;
      gettimeofday(&tv, NULL);
      lutmp.ut_tv.tv_sec = tv.tv_sec;
      lutmp.ut_tv.tv_usec = tv.tv_usec;
    }
#endif

    updwtmp(_PATH_WTMP, &lutmp);
}

#if 0
/* This is enabled in uClibc/libc/misc/utmp/wtent.c */
void updwtmp(const char *wtmp_file, const struct utmp *lutmp)
{
    int fd;

    fd = open(wtmp_file, O_APPEND | O_WRONLY);
    if (fd >= 0) {
	if (lockf(fd, F_LOCK, 0) == 0) {
	    write(fd, lutmp, sizeof(*lutmp));
	    lockf(fd, F_ULOCK, 0);
	    close(fd);
	}
    }
}
#endif