devlogoutput.c

/*
 * SNOOPY COMMAND LOGGER
 *
 * File: snoopy/output/devlogoutput.c
 *
 * Copyright (c) 2014-2015 Bostjan Skufca (bostjan _A_T_ a2o.si)
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * 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.
 */



/*
 * Includes order: from local to global
 */
#include "devlogoutput.h"

#include "snoopy.h"
#include "configuration.h"
#include "message.h"
#include "output/socketoutput.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>



/*
 * SNOOPY OUTPUT: devlogoutput
 *
 * Description:
 *     Sends given message directly to /dev/log socket, without using syslog() syscall
 *
 * Params:
 *     message:    message to send
 *     arg:        output argument(s)
 *
 * Return:
 *     int:        See snoopy.h (SNOOPY_OUTPUT_*) for details.
 */
int snoopy_output_devlogoutput (char const * const logMessage, __attribute__((unused)) char const * const arg)
{
    /* Dispatch only if non-zero size */
    if (0 == strlen(logMessage)) {
        return SNOOPY_OUTPUT_GRACEFUL_DISCARD;
    }

    /* Get config pointer */
    const snoopy_configuration_t * CFG = snoopy_configuration_get();

    /* Generate syslog ident string */
    char syslogIdent[SNOOPY_SYSLOG_IDENT_FORMAT_BUF_SIZE] = {'\0'};
    snoopy_message_generateFromFormat(syslogIdent, SNOOPY_SYSLOG_IDENT_FORMAT_BUF_SIZE, SNOOPY_SYSLOG_IDENT_FORMAT_BUF_SIZE, CFG->syslog_ident_format);

    /* Allocate buffer */
    size_t logMessageWithPrefixSize = strlen(logMessage) + SNOOPY_SYSLOG_IDENT_FORMAT_BUF_SIZE + 100;   // +100 ought to be enough for... whatever :)
    char * logMessageWithPrefix = malloc(logMessageWithPrefixSize);
    logMessageWithPrefix[0] = '\0';

    /* Generate final message - add prefix which is otherwise added by syslog() syscall */
    snprintf(
        logMessageWithPrefix,
        logMessageWithPrefixSize,
        "<%d>%.*s[%d]: %s",
        CFG->syslog_facility | CFG->syslog_level,
        SNOOPY_SYSLOG_IDENT_FORMAT_BUF_SIZE-1,
        syslogIdent,
        getpid(),
        logMessage
    );

    /* Pass execution to another output provider */
    int bytesWritten = snoopy_output_socketoutput(logMessageWithPrefix, "/dev/log");
    free(logMessageWithPrefix);
    return bytesWritten;
}