source: code/logger.c@ 55923b7

/*
 * Copyright (c) 2014 Mike Belopuhov
 * Copyright (c) 2009 Michael Shalayeff
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER IN
 * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/param.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <sys/uio.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>
#include <syslog.h>
#include <sysexits.h>
#include <login_cap.h>
#include <event.h>
#include <pwd.h>
#include <netdb.h>

#include "icb.h"
#include "icbd.h"

void logger_dispatch(int, short, void *);

int logger_pipe;

struct icbd_logentry {
        time_t  timestamp;
        char    group[ICB_MAXGRPLEN];
        char    nick[ICB_MAXNICKLEN];
        size_t  length;
};

int
logger_init(void)
{
        static struct event ev;
        struct passwd *pw;
        int pipes[2];

        if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pipes) == -1) {
                syslog(LOG_ERR, "socketpair: %m");
                exit(EX_OSERR);
        }

        switch (fork()) {
        case -1:
                syslog(LOG_ERR, "fork: %m");
                exit(EX_OSERR);
        case 0:
                break;

        default:
                close(pipes[1]);
                logger_pipe = pipes[0];
                return (0);
        }

        setproctitle("logger");
        close(pipes[0]);

        if ((pw = getpwnam(ICBD_USER)) == NULL) {
                syslog(LOG_ERR, "No passwd entry for %s", ICBD_USER);
                exit(EX_NOUSER);
        }

        if (setusercontext(NULL, pw, pw->pw_uid,
            LOGIN_SETALL & ~LOGIN_SETUSER) < 0)
                exit(EX_NOPERM);

        if (setuid(pw->pw_uid) < 0) {
                syslog(LOG_ERR, "%d: %m", pw->pw_uid);
                exit(EX_NOPERM);
        }

        if (chdir(pw->pw_dir) < 0) {
                syslog(LOG_ERR, "chdir: %m");
                exit(EX_UNAVAILABLE);
        }

        event_init();

        /* event for message processing */
        event_set(&ev, pipes[1], EV_READ | EV_PERSIST, logger_dispatch, NULL);
        if (event_add(&ev, NULL) < 0) {
                syslog(LOG_ERR, "event_add: %m");
                exit (EX_UNAVAILABLE);
        }

        return event_dispatch();
}

void
logger_dispatch(int fd, short event, void *arg __attribute__((unused)))
{
        char buf[512];
        struct icbd_logentry e;
        struct iovec iov[2];

        if (event != EV_READ)
                return;

        bzero(&e, sizeof e);
        iov[0].iov_base = &e;
        iov[0].iov_len = sizeof e;

        iov[1].iov_base = buf;
        iov[1].iov_len = sizeof buf;

        if (readv(fd, iov, 2) < (ssize_t)sizeof e) {
                syslog(LOG_ERR, "logger read: %m");
                exit(EX_DATAERR);
        }

        /* XXX */
        if (iov[1].iov_len < e.length) {
                syslog(LOG_ERR, "logger read %lu out of %lu",
                    iov[1].iov_len, e.length);
        }

        /* TODO: check time of the day and open the next file */

        fprintf(stderr, "%s@%s: %s\n", e.nick, e.group, buf);
}

void
logger(time_t timestamp, char *group, char *nick, char *what)
{
        struct icbd_logentry e;
        struct iovec iov[2];

        e.timestamp = timestamp;
        strlcpy(e.group, group, ICB_MAXGRPLEN);
        strlcpy(e.nick, nick, ICB_MAXNICKLEN);
        e.length = strlen(what) + 1;

        iov[0].iov_base = &e;
        iov[0].iov_len = sizeof e;

        iov[1].iov_base = what;
        iov[1].iov_len = e.length;

        if (writev(logger_pipe, iov, 2) == -1)
                syslog(LOG_ERR, "logger write: %m");
}