KSPowerAssertion.h

## KSPowerAssertion.h
//
//  KSPowerAssertion.h
//  Sandvox
//
//  Created by Mike on 04/08/2012.
//  Copyright (c) 2012 Karelia Software. All rights reserved.
//

#import <Foundation/Foundation.h>
#import <IOKit/pwr_mgt/IOPMLib.h>


extern NSString *KSIOReturnErrorDomain;


@interface KSPowerAssertion : NSObject
{
  @private
    IOPMAssertionID _assertionID;
}

/**
 Creates a power assertion.

 @param type The type of power assertion to create, e.g. `kIOPMAssertionTypeNoIdleSleep`.
 @param name A string that describes the name of the caller and the activity being handled by this assertion (e.g. "Mail Compacting Mailboxes"). Name may be no longer than 128 characters.
 @param error Filled in with a `KSIOReturnErrorDomain` error, should creating the assertion fail.
 @result An object encapsulating the power assertion, or `nil` in the event of failure.
 */
- (id)initWithType:(CFStringRef)type name:(NSString *)name error:(NSError **)error __attribute((nonnull(1,2)));

@end

## KSPowerAssertion.m
//
//  KSPowerAssertion.m
//  Sandvox
//
//  Created by Mike on 04/08/2012.
//  Copyright (c) 2012 Karelia Software. All rights reserved.
//

#import "KSPowerAssertion.h"


NSString *KSIOReturnErrorDomain = @"com.apple.framework.IOKit.IOReturn";


@implementation KSPowerAssertion

- (id)initWithType:(CFStringRef)type name:(NSString *)name error:(NSError **)error;
{
    if (self = [self init])
    {
        IOReturn result = IOPMAssertionCreateWithName(type,
                                                      kIOPMAssertionLevelOn,
                                                      (CFStringRef)name,
                                                      &_assertionID);

        if (result != kIOReturnSuccess)
        {
            [self release]; self = nil;
            if (error)
            {
                *error = [NSError errorWithDomain:KSIOReturnErrorDomain code:result userInfo:nil];
            }
        }
    }

    return self;
}

- (void)dealloc;
{
    // It would be very very weird for cancellation to fail, so best bet seems to be to log it
    IOReturn released = IOPMAssertionRelease(_assertionID);
    if (released != kIOReturnSuccess)
    {
        NSLog(@"Re-enabling idle sleep failed: error %i", released);
    }

    [super dealloc];
}

@end

## LICENSE.txt
Created by Mike Abdullah on 04/08/2012.
Copyright © 2012 Karelia Software

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.