sync.c

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static int 
ProcSyncDispatch(client)
    ClientPtr       client;
{
    REQUEST(xReq);

    switch (stuff->data)
    {

      case X_SyncInitialize:
	return ProcSyncInitialize(client);
      case X_SyncListSystemCounters:
	return ProcSyncListSystemCounters(client);
      case X_SyncCreateCounter:
	return ProcSyncCreateCounter(client);
      case X_SyncSetCounter:
	return ProcSyncSetCounter(client);
      case X_SyncChangeCounter:
	return ProcSyncChangeCounter(client);
      case X_SyncQueryCounter:
	return ProcSyncQueryCounter(client);
      case X_SyncDestroyCounter:
	return ProcSyncDestroyCounter(client);
      case X_SyncAwait:
	return ProcSyncAwait(client);
      case X_SyncCreateAlarm:
	return ProcSyncCreateAlarm(client);
      case X_SyncChangeAlarm:
	return ProcSyncChangeAlarm(client);
      case X_SyncQueryAlarm:
	return ProcSyncQueryAlarm(client);
      case X_SyncDestroyAlarm:
	return ProcSyncDestroyAlarm(client);
      case X_SyncSetPriority:
	return ProcSyncSetPriority(client);
      case X_SyncGetPriority:
	return ProcSyncGetPriority(client);
      default:
	return BadRequest;
    }
}

/*
 * Boring Swapping stuff ...
 */

static int 
SProcSyncInitialize(client)
    ClientPtr       client;
{
    REQUEST(xSyncInitializeReq);
    register char   n;

    swaps(&stuff->length, n);
    REQUEST_SIZE_MATCH (xSyncInitializeReq);

    return ProcSyncInitialize(client);
}

static int 
SProcSyncListSystemCounters(client)
    ClientPtr       client;
{
    REQUEST(xSyncListSystemCountersReq);
    register char   n;

    swaps(&stuff->length, n);
    REQUEST_SIZE_MATCH (xSyncListSystemCountersReq);

    return ProcSyncListSystemCounters(client);
}

static int 
SProcSyncCreateCounter(client)
    ClientPtr       client;
{
    REQUEST(xSyncCreateCounterReq);
    register char   n;

    swaps(&stuff->length, n);
    REQUEST_SIZE_MATCH (xSyncCreateCounterReq);
    swapl(&stuff->cid, n);
    swapl(&stuff->initial_value_lo, n);
    swapl(&stuff->initial_value_hi, n);

    return ProcSyncCreateCounter(client);
}

static int 
SProcSyncSetCounter(client)
    ClientPtr       client;
{
    REQUEST(xSyncSetCounterReq);
    register char   n;

    swaps(&stuff->length, n);
    REQUEST_SIZE_MATCH (xSyncSetCounterReq);
    swapl(&stuff->cid, n);
    swapl(&stuff->value_lo, n);
    swapl(&stuff->value_hi, n);

    return ProcSyncSetCounter(client);
}

static int 
SProcSyncChangeCounter(client)
    ClientPtr       client;
{
    REQUEST(xSyncChangeCounterReq);
    register char   n;

    swaps(&stuff->length, n);
    REQUEST_SIZE_MATCH (xSyncChangeCounterReq);
    swapl(&stuff->cid, n);
    swapl(&stuff->value_lo, n);
    swapl(&stuff->value_hi, n);

    return ProcSyncChangeCounter(client);
}

static int 
SProcSyncQueryCounter(client)
    ClientPtr       client;
{
    REQUEST(xSyncQueryCounterReq);
    register char   n;

    swaps(&stuff->length, n);
    REQUEST_SIZE_MATCH (xSyncQueryCounterReq);
    swapl(&stuff->counter, n);

    return ProcSyncQueryCounter(client);
}

static int 
SProcSyncDestroyCounter(client)
    ClientPtr       client;
{
    REQUEST(xSyncDestroyCounterReq);
    register char   n;

    swaps(&stuff->length, n);
    REQUEST_SIZE_MATCH (xSyncDestroyCounterReq);
    swapl(&stuff->counter, n);

    return ProcSyncDestroyCounter(client);
}

static int 
SProcSyncAwait(client)
    ClientPtr       client;
{
    REQUEST(xSyncAwaitReq);
    register char   n;

    swaps(&stuff->length, n);
    REQUEST_AT_LEAST_SIZE(xSyncAwaitReq);
    SwapRestL(stuff);

    return ProcSyncAwait(client);
}


static int 
SProcSyncCreateAlarm(client)
    ClientPtr       client;
{
    REQUEST(xSyncCreateAlarmReq);
    register char   n;

    swaps(&stuff->length, n);
    REQUEST_AT_LEAST_SIZE(xSyncCreateAlarmReq);
    swapl(&stuff->id, n);
    swapl(&stuff->valueMask, n);
    SwapRestL(stuff);

    return ProcSyncCreateAlarm(client);
}

static int 
SProcSyncChangeAlarm(client)
    ClientPtr       client;
{
    REQUEST(xSyncChangeAlarmReq);
    register char   n;

    swaps(&stuff->length, n);
    REQUEST_AT_LEAST_SIZE(xSyncChangeAlarmReq);
    swapl(&stuff->alarm, n);
    swapl(&stuff->valueMask, n);
    SwapRestL(stuff);
    return ProcSyncChangeAlarm(client);
}

static int 
SProcSyncQueryAlarm(client)
    ClientPtr       client;
{
    REQUEST(xSyncQueryAlarmReq);
    register char   n;

    swaps(&stuff->length, n);
    REQUEST_SIZE_MATCH (xSyncQueryAlarmReq);
    swapl(&stuff->alarm, n);

    return ProcSyncQueryAlarm(client);
}

static int 
SProcSyncDestroyAlarm(client)
    ClientPtr       client;
{
    REQUEST(xSyncDestroyAlarmReq);
    register char   n;

    swaps(&stuff->length, n);
    REQUEST_SIZE_MATCH (xSyncDestroyAlarmReq);
    swapl(&stuff->alarm, n);

    return ProcSyncDestroyAlarm(client);
}

static int 
SProcSyncSetPriority(client)
    ClientPtr       client;
{
    REQUEST(xSyncSetPriorityReq);
    register char   n;

    swaps(&stuff->length, n);
    REQUEST_SIZE_MATCH (xSyncSetPriorityReq);
    swapl(&stuff->id, n);
    swapl(&stuff->priority, n);

    return ProcSyncSetPriority(client);
}

static int 
SProcSyncGetPriority(client)
    ClientPtr       client;
{
    REQUEST(xSyncGetPriorityReq);
    register char   n;

    swaps(&stuff->length, n);
    REQUEST_SIZE_MATCH (xSyncGetPriorityReq);
    swapl(&stuff->id, n);

    return ProcSyncGetPriority(client);
}


static int 
SProcSyncDispatch(client)
    ClientPtr       client;
{
    REQUEST(xReq);

    switch (stuff->data)
    {
      case X_SyncInitialize:
	return SProcSyncInitialize(client);
      case X_SyncListSystemCounters:
	return SProcSyncListSystemCounters(client);
      case X_SyncCreateCounter:
	return SProcSyncCreateCounter(client);
      case X_SyncSetCounter:
	return SProcSyncSetCounter(client);
      case X_SyncChangeCounter:
	return SProcSyncChangeCounter(client);
      case X_SyncQueryCounter:
	return SProcSyncQueryCounter(client);
      case X_SyncDestroyCounter:
	return SProcSyncDestroyCounter(client);
      case X_SyncAwait:
	return SProcSyncAwait(client);
      case X_SyncCreateAlarm:
	return SProcSyncCreateAlarm(client);
      case X_SyncChangeAlarm:
	return SProcSyncChangeAlarm(client);
      case X_SyncQueryAlarm:
	return SProcSyncQueryAlarm(client);
      case X_SyncDestroyAlarm:
	return SProcSyncDestroyAlarm(client);
      case X_SyncSetPriority:
	return SProcSyncSetPriority(client);
      case X_SyncGetPriority:
	return SProcSyncGetPriority(client);
      default:
	return BadRequest;
    }
}

/*
 * Event Swapping
 */

static void 
SCounterNotifyEvent(from, to)
    xSyncCounterNotifyEvent *from, *to;
{
    to->type = from->type;
    to->kind = from->kind;
    cpswaps(from->sequenceNumber, to->sequenceNumber);
    cpswapl(from->counter, to->counter);
    cpswapl(from->wait_value_lo, to->wait_value_lo);
    cpswapl(from->wait_value_hi, to->wait_value_hi);
    cpswapl(from->counter_value_lo, to->counter_value_lo);
    cpswapl(from->counter_value_hi, to->counter_value_hi);
    cpswapl(from->time, to->time);
    cpswaps(from->count, to->count);
    to->destroyed = from->destroyed;
}


static void 
SAlarmNotifyEvent(from, to)
    xSyncAlarmNotifyEvent *from, *to;
{
    to->type = from->type;
    to->kind = from->kind;
    cpswaps(from->sequenceNumber, to->sequenceNumber);
    cpswapl(from->alarm, to->alarm);
    cpswapl(from->counter_value_lo, to->counter_value_lo);
    cpswapl(from->counter_value_hi, to->counter_value_hi);
    cpswapl(from->alarm_value_lo, to->alarm_value_lo);
    cpswapl(from->alarm_value_hi, to->alarm_value_hi);
    cpswapl(from->time, to->time);
    to->state = from->state;
}

/*
 * ** Close everything down. ** This is fairly simple for now.
 */
/* ARGSUSED */
static void 
SyncResetProc(extEntry)
    ExtensionEntry *extEntry;
{
    xfree(SysCounterList);
    SysCounterList = NULL;
    RTCounter = 0;
}


/*
 * ** Initialise the extension.
 */
void 
SyncExtensionInit()
{
    ExtensionEntry *extEntry;

    if (RTCounter == 0)
    {
	RTCounter = CreateNewResourceType(FreeCounter);
    }
    RTAlarm = CreateNewResourceType(FreeAlarm);
    RTAwait = CreateNewResourceType(FreeAwait)|RC_NEVERRETAIN;
    RTAlarmClient = CreateNewResourceType(FreeAlarmClient)|RC_NEVERRETAIN;

    if (RTCounter == 0 || RTAwait == 0 || RTAlarm == 0 ||
	RTAlarmClient == 0 ||
	(extEntry = AddExtension(SYNC_NAME,
				 XSyncNumberEvents, XSyncNumberErrors,
				 ProcSyncDispatch, SProcSyncDispatch,
				 SyncResetProc,
				 StandardMinorOpcode)) == NULL)
    {
	ErrorF("Sync Extension %d.%d failed to Initialise\n",
		SYNC_MAJOR_VERSION, SYNC_MINOR_VERSION);
	return;
    }

    SyncReqCode = extEntry->base;
    SyncEventBase = extEntry->eventBase;
    SyncErrorBase = extEntry->errorBase;
    EventSwapVector[SyncEventBase + XSyncCounterNotify] = (EventSwapPtr) SCounterNotifyEvent;
    EventSwapVector[SyncEventBase + XSyncAlarmNotify] = (EventSwapPtr) SAlarmNotifyEvent;

    /*
     * Although SERVERTIME is implemented by the OS layer, we initialise it
     * here because doing it in OsInit() is too early. The resource database
     * is not initialised when OsInit() is called. This is just about OK
     * because there is always a servertime counter.
     */
    SyncInitServerTime();

#ifdef DEBUG
    fprintf(stderr, "Sync Extension %d.%d\n",
	    SYNC_MAJOR_VERSION, SYNC_MINOR_VERSION);
#endif
}


/*
 * ***** SERVERTIME implementation - should go in its own file in OS directory?
 */


#if !defined(WIN32) && !defined(MINIX) && !defined(Lynx)
#include <sys/time.h>
#endif

static pointer ServertimeCounter;
static XSyncValue Now;
static XSyncValue *pnext_time;

#define GetTime()\
{\
    unsigned long millis = GetTimeInMillis();\
    unsigned long maxis = XSyncValueHigh32(Now);\
    if (millis < XSyncValueLow32(Now)) maxis++;\
    XSyncIntsToValue(&Now, millis, maxis);\
}

/*
*** Server Block Handler
*** code inspired by multibuffer extension
 */
/*ARGSUSED*/
static void ServertimeBlockHandler(env, wt, LastSelectMask)
pointer env;
struct timeval **wt;
pointer LastSelectMask;
{
    XSyncValue delay;
    unsigned long timeout;

    if (pnext_time)
    {
        GetTime();

        if (XSyncValueGreaterOrEqual(Now, *pnext_time))
	{
            timeout = 0;
        } 
	else
	{
	    Bool overflow;
            XSyncValueSubtract(&delay, *pnext_time, Now, &overflow);
            timeout = XSyncValueLow32(delay);
        }
        AdjustWaitForDelay(wt, timeout); /* os/utils.c */
    }
}

/*
*** Wakeup Handler
 */
/*ARGSUSED*/
static void ServertimeWakeupHandler(env, rc, LastSelectMask)
pointer env;
int rc;
pointer LastSelectMask;
{
    if (pnext_time)
    {
        GetTime();

        if (XSyncValueGreaterOrEqual(Now, *pnext_time))
	{
            SyncChangeCounter(ServertimeCounter, Now);
        }
    }
}

static void
ServertimeQueryValue(pCounter, pValue_return)
    pointer pCounter;
    CARD64 *pValue_return;
{
    GetTime();
    *pValue_return = Now;
}

static void
ServertimeBracketValues(pCounter, pbracket_less, pbracket_greater)
    pointer pCounter;
    CARD64 *pbracket_less;
    CARD64 *pbracket_greater;
{
    if (!pnext_time && pbracket_greater)
    {
	RegisterBlockAndWakeupHandlers(ServertimeBlockHandler,
				       ServertimeWakeupHandler,
				       NULL);
    }
    else if (pnext_time && !pbracket_greater)
    {
	RemoveBlockAndWakeupHandlers(ServertimeBlockHandler,
				     ServertimeWakeupHandler,
				     NULL);
    }
    pnext_time = pbracket_greater;
}

static void
SyncInitServerTime()
{
    CARD64 resolution;

    XSyncIntsToValue(&Now, GetTimeInMillis(), 0);
    XSyncIntToValue(&resolution, 4);
    ServertimeCounter = SyncCreateSystemCounter("SERVERTIME", Now, resolution,
			    XSyncCounterNeverDecreases,
			    ServertimeQueryValue, ServertimeBracketValues);
    pnext_time = NULL;
}