Plugins/common/cache.c

   1 /*
   2  * Copyright (c) 2003, 2004, 2006, 2011 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_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. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24 /*
  25  * Modification History
  26  *
  27  * May 1, 2003  Allan Nathanson <ajn@apple.com>
  28  * - initial revision
  29  */
  30
  31
  32 #include <CoreFoundation/CoreFoundation.h>
  33 #include <SystemConfiguration/SystemConfiguration.h>
  34 #include <SystemConfiguration/SCPrivate.h>      // for SCLog()
  35
  36 #include "cache.h"
  37
  38
  39 static  CFMutableDictionaryRef  cached_keys     = NULL;
  40 static  CFMutableDictionaryRef  cached_set      = NULL;
  41 static  CFMutableArrayRef       cached_removals = NULL;
  42 static  CFMutableArrayRef       cached_notifys  = NULL;
  43
  44
  45 __private_extern__
  46 void
  47 cache_open(void)
  48 {
  49         cached_keys     = CFDictionaryCreateMutable(NULL,
  50                                                     0,
  51                                                     &kCFTypeDictionaryKeyCallBacks,
  52                                                     &kCFTypeDictionaryValueCallBacks);
  53         cached_set      = CFDictionaryCreateMutable(NULL,
  54                                                     0,
  55                                                     &kCFTypeDictionaryKeyCallBacks,
  56                                                     &kCFTypeDictionaryValueCallBacks);
  57         cached_removals = CFArrayCreateMutable(NULL,
  58                                                0,
  59                                                &kCFTypeArrayCallBacks);
  60         cached_notifys  = CFArrayCreateMutable(NULL,
  61                                                0,
  62                                                &kCFTypeArrayCallBacks);
  63
  64         return;
  65 }
  66
  67
  68 __private_extern__
  69 CFPropertyListRef
  70 cache_SCDynamicStoreCopyValue(SCDynamicStoreRef store, CFStringRef key)
  71 {
  72         CFPropertyListRef       value;
  73
  74         value = CFDictionaryGetValue(cached_set, key);
  75         if (value) {
  76                 // if we have "set" a new value
  77                 return (CFRetain(value));
  78         }
  79
  80         if (CFArrayContainsValue(cached_removals,
  81                                  CFRangeMake(0, CFArrayGetCount(cached_removals)),
  82                                  key)) {
  83                 // if we have "removed" the key
  84                 _SCErrorSet(kSCStatusNoKey);
  85                 return NULL;
  86         }
  87
  88         value = CFDictionaryGetValue(cached_keys, key);
  89         if (value) {
  90                 // if we have a cached value
  91                 return (CFRetain(value));
  92         }
  93
  94         value = SCDynamicStoreCopyValue(store, key);
  95         if (value) {
  96                 CFDictionarySetValue(cached_keys, key, value);
  97         }
  98
  99         return value;
 100 }
 101
 102
 103 __private_extern__
 104 void
 105 cache_SCDynamicStoreSetValue(SCDynamicStoreRef store, CFStringRef key, CFPropertyListRef value)
 106 {
 107         CFIndex i;
 108
 109         i = CFArrayGetFirstIndexOfValue(cached_removals,
 110                                         CFRangeMake(0, CFArrayGetCount(cached_removals)),
 111                                         key);
 112         if (i != kCFNotFound) {
 113                 // if previously "removed"
 114                 CFArrayRemoveValueAtIndex(cached_removals, i);
 115         }
 116
 117         CFDictionarySetValue(cached_set, key, value);
 118
 119         return;
 120 }
 121
 122 __private_extern__
 123 void
 124 cache_SCDynamicStoreRemoveValue(SCDynamicStoreRef store, CFStringRef key)
 125 {
 126         CFDictionaryRemoveValue(cached_set, key);
 127
 128         if (!CFArrayContainsValue(cached_removals,
 129                                   CFRangeMake(0, CFArrayGetCount(cached_removals)),
 130                                   key)) {
 131                 CFArrayAppendValue(cached_removals, key);
 132         }
 133
 134         return;
 135 }
 136
 137
 138 __private_extern__
 139 void
 140 cache_SCDynamicStoreNotifyValue(SCDynamicStoreRef store, CFStringRef key)
 141 {
 142         if (!CFArrayContainsValue(cached_notifys,
 143                                   CFRangeMake(0, CFArrayGetCount(cached_notifys)),
 144                                   key)) {
 145                 CFArrayAppendValue(cached_notifys, key);
 146         }
 147
 148         return;
 149 }
 150
 151
 152 __private_extern__
 153 void
 154 cache_write(SCDynamicStoreRef store)
 155 {
 156         if ((CFDictionaryGetCount(cached_set) > 0) ||
 157             (CFArrayGetCount(cached_removals) > 0) ||
 158             (CFArrayGetCount(cached_notifys)  > 0)) {
 159                 if (!SCDynamicStoreSetMultiple(store,
 160                                  cached_set,
 161                                  cached_removals,
 162                                  cached_notifys)) {
 163                         SCLog(TRUE,
 164                               LOG_ERR,
 165                               CFSTR("SCDynamicStoreSetMultiple() failed: %s"),
 166                               SCErrorString(SCError()));
 167                 }
 168         }
 169
 170         return;
 171 }
 172
 173
 174 __private_extern__
 175 void
 176 cache_close(void)
 177 {
 178         CFRelease(cached_keys);
 179         CFRelease(cached_set);
 180         CFRelease(cached_removals);
 181         CFRelease(cached_notifys);
 182
 183         return;
 184 }