#pragma ident "$Id: log.c,v 1.1 2004/03/16 23:19:55 kohler Exp $"
/*======================================================================
 *
 *  Message logging facility.
 *
 *  The rtp_loginit() function must be called prior to rtp_log().
 *
 *  MT-safe, in the crudest possible way.
 *
 *====================================================================*/
#include "rtp.h"

#define STRLEN  64
#define HOSTNAMLEN 128
#define LOGBUFLEN  ((size_t) 20480)
#define DEFTIMEFMT "%Y:%j-%H:%M:%S"

static char *Tfmt = DEFTIMEFMT;
static char *LogFileName = (char *) NULL;
static char Prefix[LOGBUFLEN];
static char Hostname[HOSTNAMLEN];
static char Message[LOGBUFLEN];
static char buf1[LOGBUFLEN], buf2[LOGBUFLEN];
static char *Crnt_msg, *Prev_msg;
static int Pid;
static int Count = 0;
static int Facility;
static UINT16 Threshold = RTP_DEFAULT_LOG;
static MUTEX Mutex = MUTEX_INITIALIZER;

static BOOL Initialized   = FALSE;
static BOOL using_syslogd = FALSE;

/* Set the current log level */

VOID rtp_loglevel(UINT16 newlevel)
{
    Threshold = newlevel;
}

/*  Open log file  */

static FILE *open_log_file()
{
    if (using_syslogd) return (FILE *) NULL;
    if (LogFileName == (CHAR *) NULL)           return stderr;
    if (strcasecmp(LogFileName, "stderr") == 0) return stderr;
    if (strcasecmp(LogFileName, "stdout") == 0) return stdout;
    if (strcasecmp(LogFileName, "-")      == 0) return stdout;
    return fopen(LogFileName, "a+");
}

/* Flush log (close, then reopen) OBSOLETE */

void rtp_flushlog()
{
    return;
}

BOOL rtp_loginit(CHAR *file, UINT16 facility, CHAR *tfmt, CHAR *fmt, ...)
{
va_list ap;
char *ptr;

    MUTEX_LOCK(&Mutex);

    /* Should only be called once per program */

        if (Initialized) {
            errno = EALREADY;
            MUTEX_UNLOCK(&Mutex);
            return FALSE;
        }

        gethostname(Hostname, HOSTNAMLEN);
        Pid = getpid();

    /* Initilize system logger, if using syslogd */

    /*  Save facility, name, and time format string */

        Facility = facility;

        if (file != (CHAR *) NULL) {
#ifdef HAVE_SYSLOGD
            if (strcasecmp(file, "syslogd") == 0) {
                openlog(NULL, LOG_CONS, Facility);
                using_syslogd = TRUE;
            } else
#endif /* HAVE_SYSLOGD */
            if ((LogFileName = strdup(file)) == (char *) NULL) {
                MUTEX_UNLOCK(&Mutex);
                return FALSE;
            }
        }

        if (tfmt != NULL && (Tfmt = strdup(tfmt)) == NULL) {
            MUTEX_UNLOCK(&Mutex);
            return FALSE;
        }

    /*  Initialize the message buffers  */

        memset((void *) buf1, 0, LOGBUFLEN); Crnt_msg = buf1;
        memset((void *) buf2, 0, LOGBUFLEN); Prev_msg = buf2;

    /*  Create the message prefix  */

        memset((void *) Prefix, 0, LOGBUFLEN);
        if (fmt != (char *) NULL) {
            ptr = Prefix;
            va_start(ap, fmt);
            vsprintf(ptr, fmt, ap);
            va_end(ap);
        } else {
            Prefix[0] = (char) 0;
        }

    /* Initialization complete */

        Initialized = TRUE;

    MUTEX_UNLOCK(&Mutex);

    return TRUE;

}

VOID rtp_log(UINT16 level, CHAR *fmt, ...)
{
INT32 i;
va_list ap;
CHAR *ptr;
FILE *fp;
static time_t ltime;
static CHAR preamble[LOGBUFLEN];
static CHAR timstr[STRLEN];

    MUTEX_LOCK(&Mutex);

/* If we haven't been initialized, don't do anything */

    if (!Initialized) {
        MUTEX_UNLOCK(&Mutex);
        return;
    }

/* If our verbosity level is too low for this message, ignore it */

    if (Threshold < level) {
        MUTEX_UNLOCK(&Mutex);
        return;
    }

/*  Build the message string  */

    memset((void *) Crnt_msg, 0, LOGBUFLEN);
    if (using_syslogd) {
        sprintf(Crnt_msg, "%s[%d]: ", Prefix, Pid);
        ptr = Crnt_msg + strlen(Crnt_msg);
    } else {
        ptr = Crnt_msg;
    }

    va_start(ap, fmt);
    vsprintf(ptr, fmt, ap);
    va_end(ap);

/*  Strip off any trailing newlines */

    for (i = strlen(Crnt_msg) - 1; i >= 0 && Crnt_msg[i] == '\n'; i--) {
        Crnt_msg[i] = 0;
    }

/*  If using syslogd then we are done  */

#ifdef HAVE_SYSLOGD
    if (using_syslogd) {
        syslog(LOG_INFO, Crnt_msg);
        MUTEX_UNLOCK(&Mutex);
        return;
    }
#endif /* HAVE_SYSLOGD */

/*  Don't print duplicate messages  */

    if (strcmp(Crnt_msg, Prev_msg) == 0) {
        ++Count;
        MUTEX_UNLOCK(&Mutex);
        return;
    }

/*  Build the message preamble  */

    ltime = time(NULL);

    if (strftime(timstr, STRLEN, Tfmt, localtime(&ltime))) {
        sprintf(preamble, "%s ", timstr);
    } else {
        sprintf(preamble, "CAN'T DETERMINE TIME STRING! ");
    }

    sprintf(preamble + strlen(preamble), "%s ",  Hostname);
    sprintf(preamble + strlen(preamble), "%s",   Prefix);
    sprintf(preamble + strlen(preamble), "[%d]", Pid);

/*  Print the message  */

    if ((fp = open_log_file()) == (FILE *) NULL) return;
    if (Count > 1) {
        fprintf(fp, "%s ", preamble);
        fprintf(fp, "previous message repeated %d times\n", Count);
        Count = 0;
    }
    fprintf(fp, "%s %s\n", preamble, Crnt_msg);
    fflush(fp);
    if (fp != stderr && fp != stdout) fclose(fp);

/*  Save this message for comparison with the next one  */

    ptr      = Prev_msg;
    Prev_msg = Crnt_msg;
    Crnt_msg = ptr;

    MUTEX_UNLOCK(&Mutex);
    return;
}

#ifdef DEBUG_TEST

main(int argc, char **argv)
{
int i;

    if (argc != 2) {
        fprintf(stderr, "usage: %s logfilename\n", argv[0]);
        exit(1);
    }

    if (strcmp(argv[1], "syslogd") == 0) {
        rtp_loginit(argv[1], LOG_LOCAL1, NULL, argv[0]);
    } else {
        rtp_loginit(argv[1], 0, NULL, argv[0]);
    }

    for (i = 0; i < 1024; i++) rtp_log(RTP_INFO, "duplicate message\n");

    while (1) {
        rtp_log(RTP_INFO, "log entry %d\n", i++);
        sleep(1);
    }
}
#endif

/* Revision History
 *
 * $Log: log.c,v $
 * Revision 1.1  2004/03/16 23:19:55  kohler
 * Initial revision
 *
 * Revision 1.2  2002/01/18 17:57:48  nobody
 * replaced WORD, BYTE, LONG, etc macros with size specific equivalents
 * changed interpretation of unit ID from BCD to binary
 *
 * Revision 1.1.1.1  2000/06/22 19:13:09  nobody
 * Import existing sources into CVS
 *
 */
