/*
 * Copyright (C) 1998 NCSA
 *		    All rights reserved.
 *
 * Programmer:	Robb Matzke <matzke@llnl.gov>
 *		Friday, July 24, 1998
 *
 * Purpose:	The object modification time message.
 */
#include <H5private.h>
#include <H5Eprivate.h>
#include <H5MMprivate.h>
#include <H5Oprivate.h>

#define PABLO_MASK	H5O_mtime_mask

static void *H5O_mtime_decode(H5F_t *f, const uint8 *p, H5O_shared_t *sh);
static herr_t H5O_mtime_encode(H5F_t *f, uint8 *p, const void *_mesg);
static void *H5O_mtime_copy(const void *_mesg, void *_dest);
static size_t H5O_mtime_size(H5F_t *f, const void *_mesg);
static herr_t H5O_mtime_debug(H5F_t *f, const void *_mesg, FILE *stream,
			     intn indent, intn fwidth);

/* This message derives from H5O */
const H5O_class_t H5O_MTIME[1] = {{
    H5O_MTIME_ID,		/*message id number		*/
    "mtime",			/*message name for debugging	*/
    sizeof(time_t),		/*native message size		*/
    H5O_mtime_decode,		/*decode message		*/
    H5O_mtime_encode,		/*encode message		*/
    H5O_mtime_copy,		/*copy the native value		*/
    H5O_mtime_size,		/*raw message size		*/
    NULL,			/*free internal memory		*/
    NULL,			/*get share method		*/
    NULL,			/*set share method		*/
    H5O_mtime_debug,		/*debug the message		*/
}};

/* Interface initialization */
static hbool_t interface_initialize_g = FALSE;
#define INTERFACE_INIT	NULL


/*-------------------------------------------------------------------------
 * Function:	H5O_mtime_decode
 *
 * Purpose:	Decode a modification time message and return a pointer to a
 *		new time_t value.
 *
 * Return:	Success:	Ptr to new message in native struct.
 *
 *		Failure:	NULL
 *
 * Programmer:	Robb Matzke
 *		matzke@llnl.gov
 *		Jul 24 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
static void *
H5O_mtime_decode(H5F_t __unused__ *f, const uint8 *p,
		 H5O_shared_t __unused__ *sh)
{
    time_t	*mesg, the_time;
    intn	i;
    struct tm	tm;
    static int	ncalls=0;

    FUNC_ENTER(H5O_mtime_decode, NULL);

    /* check args */
    assert(f);
    assert(p);
    assert (!sh);

    /* Initialize time zone information */
    if (0==ncalls++) HDtzset();

    /* decode */
    for (i=0; i<14; i++) {
	if (!HDisdigit(p[i])) {
	    HRETURN_ERROR(H5E_OHDR, H5E_CANTINIT, NULL,
			  "badly formatted modification time message");
	}
    }

    /*
     * Convert YYYYMMDDhhmmss UTC to a time_t.  This is a little problematic
     * because mktime() operates on local times.  We convert to local time
     * and then figure out the adjustment based on the local time zone and
     * daylight savings setting.
     */
    HDmemset(&tm, 0, sizeof tm);
    tm.tm_year = (p[0]-'0')*1000 + (p[1]-'0')*100 +
		 (p[2]-'0')*10 + (p[3]-'0') - 1900;
    tm.tm_mon = (p[4]-'0')*10 + (p[5]-'0') - 1;
    tm.tm_mday = (p[6]-'0')*10 + (p[7]-'0');
    tm.tm_hour = (p[8]-'0')*10 + (p[9]-'0');
    tm.tm_min = (p[10]-'0')*10 + (p[11]-'0');
    tm.tm_sec = (p[12]-'0')*10 + (p[13]-'0');
    tm.tm_isdst = -1; /*figure it out*/
    if ((time_t)-1==(the_time=HDmktime(&tm))) {
	HRETURN_ERROR(H5E_OHDR, H5E_CANTINIT, NULL,
		      "badly formatted modification time message");
    }

#if defined(HAVE_TM_GMTOFF)
    /* FreeBSD, OSF 4.0 */
    the_time += tm.tm_gmtoff;
#elif defined(HAVE_TIMEZONE)
    /* Linux */
    the_time -= timezone - (tm.tm_isdst?3600:0);
#elif defined(HAVE_BSDGETTIMEOFDAY) && defined(HAVE_STRUCT_TIMEZONE)
    /* Irix5.3 */
    {
	struct timezone tz;
	if (BSDgettimeofday(NULL, &tz)<0) {
	    HRETURN_ERROR(H5E_OHDR, H5E_CANTINIT, NULL,
			  "unable to obtain local timezone information");
	}
	the_time -= tz.tz_minuteswest*60 - (tm.tm_isdst?3600:0);
    }
#elif defined(HAVE_GETTIMEOFDAY) && defined(HAVE_STRUCT_TIMEZONE)
    {
	struct timezone tz;
	if (gettimeofday(NULL, &tz)<0) {
	    HRETURN_ERROR(H5E_OHDR, H5E_CANTINIT, NULL,
			  "unable to obtain local timezone information");
	}
	the_time -= tz.tz_minuteswest*60 - (tm.tm_isdst?3600:0);
    }
#else
    /*
     * The catch-all.  If we can't convert a character string universal
     * coordinated time to a time_t value reliably then we can't decode the
     * modification time message. This really isn't as bad as it sounds --
     * the only way a user can get the modification time is from H5Gget_objinfo()
     * and H5G_get_objinfo() can gracefully recover.
     */

    /* Irix64 */
    HRETURN_ERROR(H5E_OHDR, H5E_CANTINIT, NULL,
		  "unable to obtain local timezone information");
#endif
    
    /* The return value */
    if (NULL==(mesg = H5MM_calloc(sizeof(time_t)))) {
	HRETURN_ERROR (H5E_RESOURCE, H5E_NOSPACE, NULL,
		       "memory allocation failed");
    }
    *mesg = the_time;

    FUNC_LEAVE((void*)mesg);
}


/*-------------------------------------------------------------------------
 * Function:	H5O_mtime_encode
 *
 * Purpose:	Encodes a modification time message.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *		matzke@llnl.gov
 *		Jul 24 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5O_mtime_encode(H5F_t __unused__ *f, uint8 *p, const void *_mesg)
{
    const time_t	*mesg = (const time_t *) _mesg;
    struct tm		*tm;
    

    FUNC_ENTER(H5O_mtime_encode, FAIL);

    /* check args */
    assert(f);
    assert(p);
    assert(mesg);

    /* encode */
    tm = HDgmtime(mesg);
    sprintf((char*)p, "%04d%02d%02d%02d%02d%02d",
	    1900+tm->tm_year, 1+tm->tm_mon, tm->tm_mday,
	    tm->tm_hour, tm->tm_min, tm->tm_sec);

    FUNC_LEAVE(SUCCEED);
}


/*-------------------------------------------------------------------------
 * Function:	H5O_mtime_copy
 *
 * Purpose:	Copies a message from _MESG to _DEST, allocating _DEST if
 *		necessary.
 *
 * Return:	Success:	Ptr to _DEST
 *
 *		Failure:	NULL
 *
 * Programmer:	Robb Matzke
 *		matzke@llnl.gov
 *		Jul 24 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
static void *
H5O_mtime_copy(const void *_mesg, void *_dest)
{
    const time_t	*mesg = (const time_t *) _mesg;
    time_t		*dest = (time_t *) _dest;

    FUNC_ENTER(H5O_mtime_copy, NULL);

    /* check args */
    assert(mesg);
    if (!dest && NULL==(dest = H5MM_calloc(sizeof(time_t)))) {
	HRETURN_ERROR (H5E_RESOURCE, H5E_NOSPACE, NULL,
		       "memory allocation failed");
    }
    
    /* copy */
    *dest = *mesg;

    FUNC_LEAVE((void *) dest);
}

/*-------------------------------------------------------------------------
 * Function:	H5O_mtime_size
 *
 * Purpose:	Returns the size of the raw message in bytes not
 *		counting the message type or size fields, but only the data
 *		fields.	 This function doesn't take into account
 *		alignment.
 *
 * Return:	Success:	Message data size in bytes w/o alignment.
 *
 *		Failure:	0
 *
 * Programmer:	Robb Matzke
 *		matzke@llnl.gov
 *		Jul 14 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
static size_t
H5O_mtime_size(H5F_t __unused__ *f, const void __unused__ *mesg)
{
    FUNC_ENTER(H5O_mtime_size, 0);

    /* check args */
    assert(f);
    assert(mesg);

    FUNC_LEAVE(16);
}


/*-------------------------------------------------------------------------
 * Function:	H5O_mtime_debug
 *
 * Purpose:	Prints debugging info for the message.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *		matzke@llnl.gov
 *		Jul 24 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5O_mtime_debug(H5F_t __unused__ *f, const void *_mesg, FILE *stream,
		intn indent, intn fwidth)
{
    const time_t	*mesg = (const time_t *)_mesg;
    struct tm		*tm;
    char		buf[128];
    
    FUNC_ENTER(H5O_mtime_debug, FAIL);

    /* check args */
    assert(f);
    assert(mesg);
    assert(stream);
    assert(indent >= 0);
    assert(fwidth >= 0);

    /* debug */
    tm = HDlocaltime(mesg);

    
    HDstrftime(buf, sizeof(buf), "%Y-%m-%d %H:%M:%S %Z", tm);
    fprintf(stream, "%*s%-*s %s\n", indent, "", fwidth,
	    "Time:", buf);

    FUNC_LEAVE(SUCCEED);
}

