fwknop/server/log_msg.c

/*
 *****************************************************************************
 *
 * File:    log_msg.c
 *
 * Author:  Damien S. Stuart
 *
 * Purpose: General logging routine that can write to syslog and/or stderr
 *          and can take varibale number of args.
 *
 * Copyright (C) 2009 Damien Stuart (dstuart@dstuart.org)
 *
 *  License (GNU Public License):
 *
 *     This program is distributed in the hope that it will be useful,
 *     but WITHOUT ANY WARRANTY; without even the implied warranty of
 *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *     GNU General Public License for more details.
 *
 *     You should have received a copy of the GNU General Public License
 *     along with this program; if not, write to the Free Software
 *     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
 *     USA
 *
 *****************************************************************************
*/
#include "fwknopd_common.h"
#include "log_msg.h"

/* The default log facility (can be overridden via config file directive).
*/
static int  syslog_fac      = LOG_DAEMON;

/* This value is or'ed with the log level on all logging calls. This allows
 * for force log to stderr instead of syslog simply be setting this to the
 * appropriate value (which is done at init_logging().
*/
static int  static_log_flag = 0;

/* The name to use for ID in log messages.  This defaults to fwknopd.
*/
static char *log_name = NULL;

/* Free resources allocated for logging.
*/
void
free_logging(void)
{
    if(log_name != NULL)
        free(log_name);
}

/* Initialize logging sets the name used for syslog.
*/
void
init_logging(fko_srv_options_t *opts) {
    char                   *my_name = NULL;

    /* In case this is a re-init.
    */
    free_logging();
 
    /* Allocate memory for the log_name and set the my_name to point to the
     * appropriate name. The name should already be set in the config struct
     * but if it is not, fallback to the default as defined by 'MY_NAME'.
    */
    if(opts->config[CONF_SYSLOG_IDENTITY] != NULL
      && opts->config[CONF_SYSLOG_IDENTITY][0] != '\0')
    {
        my_name  = opts->config[CONF_SYSLOG_IDENTITY];
        log_name = malloc(strlen(opts->config[CONF_SYSLOG_IDENTITY])+1);
    }
    else
    {
        my_name  = (char*)&MY_NAME;
        log_name = malloc(strlen(MY_NAME)+1);
    }

    if(log_name == NULL)
    {
        fprintf(stderr, "Memory allocation error setting log_name!\n");
        exit(EXIT_FAILURE);
    }

    /* Set our name.
    */
    strcpy(log_name, my_name);

    /* If we are running in the foreground, all logging will go to stderr.
    */
    if(opts->foreground != 0)
        static_log_flag = LOG_STDERR | LOG_STDERR_ONLY;

    /* Parse the log facility as specified in the config struct. If, for some
     * reason, it is not, fac will already be set to LOG_DAEMON.
    */
    if(opts->config[CONF_SYSLOG_FACILITY] != NULL
      && opts->config[CONF_SYSLOG_FACILITY][0] != '\0')
    {
        if(!strcasecmp(opts->config[CONF_SYSLOG_FACILITY], "LOG_DAEMON"))
            syslog_fac = LOG_DAEMON;
        else if(!strcasecmp(opts->config[CONF_SYSLOG_FACILITY], "LOG_LOCAL0"))
            syslog_fac = LOG_LOCAL0;
        else if(!strcasecmp(opts->config[CONF_SYSLOG_FACILITY], "LOG_LOCAL1"))
            syslog_fac = LOG_LOCAL1;
        else if(!strcasecmp(opts->config[CONF_SYSLOG_FACILITY], "LOG_LOCAL2"))
            syslog_fac = LOG_LOCAL2;
        else if(!strcasecmp(opts->config[CONF_SYSLOG_FACILITY], "LOG_LOCAL3"))
            syslog_fac = LOG_LOCAL3;
        else if(!strcasecmp(opts->config[CONF_SYSLOG_FACILITY], "LOG_LOCAL4"))
            syslog_fac = LOG_LOCAL4;
        else if(!strcasecmp(opts->config[CONF_SYSLOG_FACILITY], "LOG_LOCAL5"))
            syslog_fac = LOG_LOCAL5;
        else if(!strcasecmp(opts->config[CONF_SYSLOG_FACILITY], "LOG_LOCAL6"))
            syslog_fac = LOG_LOCAL6;
        else if(!strcasecmp(opts->config[CONF_SYSLOG_FACILITY], "LOG_LOCAL7"))
            syslog_fac = LOG_LOCAL7;
    }
}

/* Set the log facility value.
*/
void
set_log_facility(int fac)
{
    syslog_fac = fac;
}

/* Syslog message function.  It uses default set at intialization, and also
 * takes variable args to accomodate printf-like formatting and expansion.
*/
void
log_msg(int level, char* msg, ...)
{
    va_list ap, apse;

    va_start(ap, msg);

    level |= static_log_flag;

    /* Print msg to stderr if the level was or'ed with LOG_STDERR
    */
    if(LOG_STDERR & level)
    {
        /* Need to make a copy of our va_list so we don't screw
         * up the message going to syslog after we print it to stderr.
        */
        va_copy(apse, ap);

        vfprintf(stderr, msg, apse);
        fprintf(stderr, "\n");

        va_end(apse);

        if(LOG_STDERR_ONLY & level)
            return;

        /* Remove the log to stderr flag from the log level value.
        */
        level &= LOG_STDERR_MASK;
    }

    /* Send the message to syslog.
    */
    openlog(log_name, LOG_PID, syslog_fac);

    vsyslog(level, msg, ap);

    va_end(ap);
}

/***EOF***/