iokit/Kernel/IOPMPowerSourceList.cpp

   1 /*
   2  * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 #include <IOKit/pwr_mgt/IOPM.h>
  29 #include <IOKit/pwr_mgt/IOPMPowerSourceList.h>
  30 #include <IOKit/pwr_mgt/IOPMPowerSource.h>
  31
  32 #define super OSObject
  33 OSDefineMetaClassAndStructors(IOPMPowerSourceList, OSObject)
  34
  35 //******************************************************************************
  36 // init
  37 //
  38 //******************************************************************************
  39 void
  40 IOPMPowerSourceList::initialize( void )
  41 {
  42         firstItem = NULL;
  43         length = 0;
  44 }
  45
  46 //******************************************************************************
  47 // addToList
  48 //
  49 //******************************************************************************
  50
  51 IOReturn
  52 IOPMPowerSourceList::addToList(IOPMPowerSource *newPowerSource)
  53 {
  54         IOPMPowerSource * nextPowerSource;
  55
  56         // Is new object already in the list?
  57         nextPowerSource = firstItem;
  58         while (nextPowerSource != NULL) {
  59                 if (nextPowerSource == newPowerSource) {
  60                         // yes, just return
  61                         return IOPMNoErr;
  62                 }
  63                 nextPowerSource = nextInList(nextPowerSource);
  64         }
  65
  66         // add it to list
  67         newPowerSource->nextInList = firstItem;
  68         firstItem = newPowerSource;
  69         length++;
  70         return IOPMNoErr;
  71 }
  72
  73
  74 //******************************************************************************
  75 // firstInList
  76 //
  77 //******************************************************************************
  78
  79 IOPMPowerSource *
  80 IOPMPowerSourceList::firstInList( void )
  81 {
  82         return firstItem;
  83 }
  84
  85 //******************************************************************************
  86 // nextInList
  87 //
  88 //******************************************************************************
  89
  90 IOPMPowerSource *
  91 IOPMPowerSourceList::nextInList(IOPMPowerSource *currentItem)
  92 {
  93         if (currentItem != NULL) {
  94                 return currentItem->nextInList;
  95         }
  96         return NULL;
  97 }
  98
  99 //******************************************************************************
 100 // numberOfItems
 101 //
 102 //******************************************************************************
 103
 104 unsigned long
 105 IOPMPowerSourceList::numberOfItems( void )
 106 {
 107         return length;
 108 }
 109
 110 //******************************************************************************
 111 // removeFromList
 112 //
 113 // Find the item in the list, unlink it, and free it.
 114 //******************************************************************************
 115
 116 IOReturn
 117 IOPMPowerSourceList::removeFromList( IOPMPowerSource * theItem )
 118 {
 119         IOPMPowerSource * item = firstItem;
 120         IOPMPowerSource * temp;
 121
 122         if (NULL == item) {
 123                 goto exit;
 124         }
 125
 126         if (item == theItem) {
 127                 firstItem = item->nextInList;
 128                 length--;
 129                 item->release();
 130                 return IOPMNoErr;
 131         }
 132         while (item->nextInList != NULL) {
 133                 if (item->nextInList == theItem) {
 134                         temp = item->nextInList;
 135                         item->nextInList = temp->nextInList;
 136                         length--;
 137                         temp->release();
 138                         return IOPMNoErr;
 139                 }
 140                 item = item->nextInList;
 141         }
 142
 143 exit:
 144         return IOPMNoErr;
 145 }
 146
 147
 148 //******************************************************************************
 149 // free
 150 //
 151 // Free all items in the list, and then free the list itself
 152 //******************************************************************************
 153
 154 void
 155 IOPMPowerSourceList::free(void )
 156 {
 157         IOPMPowerSource * next = firstItem;
 158
 159         while (next != NULL) {
 160                 firstItem = next->nextInList;
 161                 length--;
 162                 next->release();
 163                 next = firstItem;
 164         }
 165         super::free();
 166 }