IOCommandGate.cpp   [plain text]

/*
 * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_OSREFERENCE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code 
 * as defined in and that are subject to the Apple Public Source License 
 * Version 2.0 (the 'License'). You may not use this file except in 
 * compliance with the License.  The rights granted to you under the 
 * License may not be used to create, or enable the creation or 
 * redistribution of, unlawful or unlicensed copies of an Apple operating 
 * system, or to circumvent, violate, or enable the circumvention or 
 * violation of, any terms of an Apple operating system software license 
 * agreement.
 *
 * Please obtain a copy of the License at 
 * http://www.opensource.apple.com/apsl/ and read it before using this 
 * file.
 *
 * The Original Code and all software distributed under the License are 
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 
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#include <IOKit/IOCommandGate.h>
#include <IOKit/IOWorkLoop.h>
#include <IOKit/IOReturn.h>
#include <IOKit/IOTimeStamp.h>

#define super IOEventSource

OSDefineMetaClassAndStructors(IOCommandGate, IOEventSource)
OSMetaClassDefineReservedUnused(IOCommandGate, 0);
OSMetaClassDefineReservedUnused(IOCommandGate, 1);
OSMetaClassDefineReservedUnused(IOCommandGate, 2);
OSMetaClassDefineReservedUnused(IOCommandGate, 3);
OSMetaClassDefineReservedUnused(IOCommandGate, 4);
OSMetaClassDefineReservedUnused(IOCommandGate, 5);
OSMetaClassDefineReservedUnused(IOCommandGate, 6);
OSMetaClassDefineReservedUnused(IOCommandGate, 7);

bool IOCommandGate::checkForWork() { return false; }

bool IOCommandGate::init(OSObject *inOwner, Action inAction)
{
    return super::init(inOwner, (IOEventSource::Action) inAction);
}

IOCommandGate *
IOCommandGate::commandGate(OSObject *inOwner, Action inAction)
{
    IOCommandGate *me = new IOCommandGate;

    if (me && !me->init(inOwner, inAction)) {
        me->release();
        return 0;
    }

    return me;
}

IOReturn IOCommandGate::runCommand(void *arg0, void *arg1,
                                   void *arg2, void *arg3)
{
    IOReturn res;

    if (!enabled)
        return kIOReturnNotPermitted;

    if (!action)
        return kIOReturnNoResources;

    // closeGate is recursive so don't worry if we already hold the lock.
    IOTimeStampConstant(IODBG_CMDQ(IOCMDQ_ACTION),
			(unsigned int) action, (unsigned int) owner);

    closeGate();
    res = (*(Action) action)(owner, arg0, arg1, arg2, arg3);
    openGate();

    return res;
}

IOReturn IOCommandGate::runAction(Action inAction,
                                  void *arg0, void *arg1,
                                  void *arg2, void *arg3)
{
    IOReturn res;

    if (!enabled)
        return kIOReturnNotPermitted;

    if (!inAction)
        return kIOReturnBadArgument;

    IOTimeStampConstant(IODBG_CMDQ(IOCMDQ_ACTION),
			(unsigned int) inAction, (unsigned int) owner);

    // closeGate is recursive so don't worry if we already hold the lock.
    closeGate();
    res = (*inAction)(owner, arg0, arg1, arg2, arg3);
    openGate();

    return res;
}

IOReturn IOCommandGate::attemptCommand(void *arg0, void *arg1,
                                       void *arg2, void *arg3)
{
    IOReturn res;

    if (!enabled)
        return kIOReturnNotPermitted;

    if (!action)
        return kIOReturnNoResources;

    // Try to hold the lock if can't get return immediately.
    if (!tryCloseGate())
        return kIOReturnCannotLock;

    // closeGate is recursive so don't worry if we already hold the lock.
    IOTimeStampConstant(IODBG_CMDQ(IOCMDQ_ACTION),
			(unsigned int) action, (unsigned int) owner);

    res = (*(Action) action)(owner, arg0, arg1, arg2, arg3);
    openGate();

    return res;
}

IOReturn IOCommandGate::attemptAction(Action inAction,
                                      void *arg0, void *arg1,
                                      void *arg2, void *arg3)
{
    IOReturn res;

    if (!enabled)
        return kIOReturnNotPermitted;

    if (!inAction)
        return kIOReturnBadArgument;

    // Try to close the gate if can't get return immediately.
    if (!tryCloseGate())
        return kIOReturnCannotLock;

    IOTimeStampConstant(IODBG_CMDQ(IOCMDQ_ACTION),
			(unsigned int) inAction, (unsigned int) owner);

    res = (*inAction)(owner, arg0, arg1, arg2, arg3);
    openGate();

    return res;
}

IOReturn IOCommandGate::commandSleep(void *event, UInt32 interruptible)
{
    if (!workLoop->inGate())
        return kIOReturnNotPermitted;

    return sleepGate(event, interruptible);
}

void IOCommandGate::commandWakeup(void *event, bool oneThread)
{
    wakeupGate(event, oneThread);
}