iokit/IOKit/IORegistryEntry.h

   1 /*
   2  * Copyright (c) 1998-2019 Apple 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,
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  23  * Please see the License for the specific language governing rights and
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  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*
  29  * Copyright (c) 1998 Apple Computer, Inc.  All rights reserved.
  30  *
  31  * HISTORY
  32  *
  33  */
  34
  35
  36 #ifndef _IOKIT_IOREGISTRYENTRY_H
  37 #define _IOKIT_IOREGISTRYENTRY_H
  38
  39 #include <IOKit/IOTypes.h>
  40 #include <libkern/c++/OSContainers.h>
  41
  42
  43 extern const OSSymbol * gIONameKey;
  44 extern const OSSymbol * gIOLocationKey;
  45 extern const OSSymbol * gIORegistryEntryIDKey;
  46 extern const OSSymbol * gIORegistryEntryPropertyKeysKey;
  47
  48 class IORegistryEntry;
  49 class IORegistryPlane;
  50 class IORegistryIterator;
  51
  52 typedef void (*IORegistryEntryApplierFunction)(IORegistryEntry * entry,
  53     void * context);
  54
  55 enum {
  56         kIORegistryIterateRecursively   = 0x00000001,
  57         kIORegistryIterateParents       = 0x00000002,
  58 };
  59
  60 #ifdef KERNEL_PRIVATE
  61 enum{
  62         kIORegistryEntryIndexedPropertyCLPC = 0,
  63         kIORegistryEntryIndexedPropertyCount,
  64 };
  65 #endif /* KERNEL_PRIVATE */
  66
  67 /*! @class IORegistryEntry : public OSObject
  68  *   @abstract The base class for all objects in the registry.
  69  *   @discussion The IORegistryEntry base class provides functions for describing graphs of connected registry entries, each with a dictionary-based property table. Entries may be connected in different planes, with differing topologies. Access to the registry is protected against multiple threads. Inside the kernel planes are specified with plane objects and are published by the creator - IOService exports the gIOServicePlane plane object for example. Non kernel clients specify planes by their name.
  70  */
  71
  72 class IORegistryEntry : public OSObject
  73 {
  74         friend class IORegistryIterator;
  75
  76         OSDeclareDefaultStructors(IORegistryEntry);
  77
  78 protected:
  79 /*! @struct ExpansionData
  80  *   @discussion This structure will be used to expand the capablilties of this class in the future.
  81  */
  82         struct ExpansionData;
  83
  84 /*! @var reserved
  85  *   Reserved for future use.  (Internal use only)  */
  86         ExpansionData * reserved;
  87
  88 private:
  89
  90         OSDictionary *      fRegistryTable;
  91         OSDictionary *      fPropertyTable;
  92
  93 public:
  94 /* methods available in Mac OS X 10.1 or later */
  95
  96 /*! @function copyProperty
  97  *   @abstract Synchronized method to obtain a property from a registry entry or one of its parents (or children) in the hierarchy. Available in Mac OS X 10.1 or later.
  98  *   @discussion This method will search for a property, starting first with this registry entry's property table, then iterating recusively through either the parent registry entries or the child registry entries of this entry. Once the first occurrence is found, it will lookup and return the value of the property, using the OSDictionary::getObject semantics. The iteration keeps track of entries that have been recursed into previously to avoid loops. This method is synchronized with other IORegistryEntry accesses to the property table(s).
  99  *   @param aKey The property's name as a C-string.
 100  *   @param plane The plane to iterate over, eg. gIOServicePlane.
 101  *   @param options kIORegistryIterateRecursively may be set to recurse automatically into the registry hierarchy. Without this option, this method degenerates into the standard getProperty() call. kIORegistryIterateParents may be set to iterate the parents of the entry, in place of the children.
 102  *   @result The property value found, or zero. A reference on any found property is returned to caller, which should be released. */
 103
 104         virtual OSObject * copyProperty( const char *           aKey,
 105             const IORegistryPlane * plane,
 106             IOOptionBits            options =
 107             kIORegistryIterateRecursively |
 108             kIORegistryIterateParents) const;
 109
 110 /*! @function copyProperty
 111  *   @abstract Synchronized method to obtain a property from a registry entry or one of its parents (or children) in the hierarchy. Available in Mac OS X 10.1 or later.
 112  *   @discussion This method will search for a property, starting first with this registry entry's property table, then iterating recusively through either the parent registry entries or the child registry entries of this entry. Once the first occurrence is found, it will lookup and return the value of the property, using the OSDictionary::getObject semantics. The iteration keeps track of entries that have been recursed into previously to avoid loops. This method is synchronized with other IORegistryEntry accesses to the property table(s).
 113  *   @param aKey The property's name as an OSString.
 114  *   @param plane The plane to iterate over, eg. gIOServicePlane.
 115  *   @param options kIORegistryIterateRecursively may be set to recurse automatically into the registry hierarchy. Without this option, this method degenerates into the standard getProperty() call. kIORegistryIterateParents may be set to iterate the parents of the entry, in place of the children.
 116  *   @result The property value found, or zero. A reference on any found property is returned to caller, which should be released. */
 117
 118         virtual OSObject * copyProperty( const OSString *        aKey,
 119             const IORegistryPlane * plane,
 120             IOOptionBits            options =
 121             kIORegistryIterateRecursively |
 122             kIORegistryIterateParents) const;
 123
 124 /*! @function copyProperty
 125  *   @abstract Synchronized method to obtain a property from a registry entry or one of its parents (or children) in the hierarchy. Available in Mac OS X 10.1 or later.
 126  *   @discussion This method will search for a property, starting first with this registry entry's property table, then iterating recusively through either the parent registry entries or the child registry entries of this entry. Once the first occurrence is found, it will lookup and return the value of the property, using the OSDictionary::getObject semantics. The iteration keeps track of entries that have been recursed into previously to avoid loops. This method is synchronized with other IORegistryEntry accesses to the property table(s).
 127  *   @param aKey The property's name as an OSSymbol.
 128  *   @param plane The plane to iterate over, eg. gIOServicePlane.
 129  *   @param options kIORegistryIterateRecursively may be set to recurse automatically into the registry hierarchy. Without this option, this method degenerates into the standard getProperty() call. kIORegistryIterateParents may be set to iterate the parents of the entry, in place of the children.
 130  *   @result The property value found, or zero. A reference on any found property is returned to caller, which should be released. */
 131
 132         virtual OSObject * copyProperty( const OSSymbol *        aKey,
 133             const IORegistryPlane * plane,
 134             IOOptionBits            options =
 135             kIORegistryIterateRecursively |
 136             kIORegistryIterateParents) const;
 137
 138 /*! @function copyParentEntry
 139  *   @abstract Returns an registry entry's first parent entry in a plane. Available in Mac OS X 10.1 or later.
 140  *   @discussion This function will return the parent to which a registry entry was first attached. Since the majority of registry entrys have only one provider, this is a useful simplification.
 141  *   @param plane The plane object.
 142  *   @result Returns the first parent of the registry entry, or zero if the entry is not attached into the registry in that plane. A reference on the entry is returned to caller, which should be released. */
 143
 144         virtual IORegistryEntry * copyParentEntry( const IORegistryPlane * plane ) const;
 145
 146 /*! @function copyChildEntry
 147  *   @abstract Returns an registry entry's first child entry in a plane. Available in Mac OS X 10.1 or later.
 148  *   @discussion This function will return the child which first attached to a registry entry.
 149  *   @param plane The plane object.
 150  *   @result Returns the first child of the registry entry, or zero if the entry is not attached into the registry in that plane. A reference on the entry is returned to caller, which should be released. */
 151
 152         virtual IORegistryEntry * copyChildEntry( const IORegistryPlane * plane ) const;
 153
 154 /* method available in Mac OS X 10.4 or later */
 155 /*!
 156  *   @typedef Action
 157  *   @discussion Type and arguments of callout C function that is used when
 158  *  a runCommand is executed by a client.  Cast to this type when you want a C++
 159  *  member function to be used.  Note the arg1 - arg3 parameters are passed straight pass through to the action callout.
 160  *   @param target
 161  *       Target of the function, can be used as a refcon.  Note if a C++ function
 162  *  was specified, this parameter is implicitly the first parameter in the target
 163  *  member function's parameter list.
 164  *   @param arg0 Argument to action from run operation.
 165  *   @param arg1 Argument to action from run operation.
 166  *   @param arg2 Argument to action from run operation.
 167  *   @param arg3 Argument to action from run operation.
 168  */
 169         typedef IOReturn (*Action)(OSObject *target,
 170             void *arg0, void *arg1,
 171             void *arg2, void *arg3);
 172
 173 /*! @function runPropertyAction
 174  *   @abstract Single thread a call to an action w.r.t. the property lock
 175  *   @discussion Client function that causes the given action to be called in a manner that syncrhonises with the registry iterators and serialisers.  This functin can be used to synchronously manipulate the property table of this nub
 176  *   @param action Pointer to function to be executed in work-loop context.
 177  *   @param arg0 Parameter for action parameter, defaults to 0.
 178  *   @param arg1 Parameter for action parameter, defaults to 0.
 179  *   @param arg2 Parameter for action parameter, defaults to 0.
 180  *   @param arg3 Parameter for action parameter, defaults to 0.
 181  *   @result Returns the value of the Action callout.
 182  */
 183         virtual IOReturn runPropertyAction(Action action, OSObject *target,
 184             void *arg0 = NULL, void *arg1 = NULL,
 185             void *arg2 = NULL, void *arg3 = NULL);
 186
 187 #ifdef __BLOCKS__
 188         typedef IOReturn (^ActionBlock)(void);
 189         IOReturn runPropertyActionBlock(ActionBlock block);
 190 #endif /* __BLOCKS__ */
 191
 192 private:
 193 #if __LP64__
 194         OSMetaClassDeclareReservedUnused(IORegistryEntry, 0);
 195         OSMetaClassDeclareReservedUnused(IORegistryEntry, 1);
 196         OSMetaClassDeclareReservedUnused(IORegistryEntry, 2);
 197         OSMetaClassDeclareReservedUnused(IORegistryEntry, 3);
 198         OSMetaClassDeclareReservedUnused(IORegistryEntry, 4);
 199         OSMetaClassDeclareReservedUnused(IORegistryEntry, 5);
 200 #else
 201         OSMetaClassDeclareReservedUsed(IORegistryEntry, 0);
 202         OSMetaClassDeclareReservedUsed(IORegistryEntry, 1);
 203         OSMetaClassDeclareReservedUsed(IORegistryEntry, 2);
 204         OSMetaClassDeclareReservedUsed(IORegistryEntry, 3);
 205         OSMetaClassDeclareReservedUsed(IORegistryEntry, 4);
 206         OSMetaClassDeclareReservedUsed(IORegistryEntry, 5);
 207 #endif
 208         OSMetaClassDeclareReservedUnused(IORegistryEntry, 6);
 209         OSMetaClassDeclareReservedUnused(IORegistryEntry, 7);
 210         OSMetaClassDeclareReservedUnused(IORegistryEntry, 8);
 211         OSMetaClassDeclareReservedUnused(IORegistryEntry, 9);
 212         OSMetaClassDeclareReservedUnused(IORegistryEntry, 10);
 213         OSMetaClassDeclareReservedUnused(IORegistryEntry, 11);
 214         OSMetaClassDeclareReservedUnused(IORegistryEntry, 12);
 215         OSMetaClassDeclareReservedUnused(IORegistryEntry, 13);
 216         OSMetaClassDeclareReservedUnused(IORegistryEntry, 14);
 217         OSMetaClassDeclareReservedUnused(IORegistryEntry, 15);
 218         OSMetaClassDeclareReservedUnused(IORegistryEntry, 16);
 219         OSMetaClassDeclareReservedUnused(IORegistryEntry, 17);
 220         OSMetaClassDeclareReservedUnused(IORegistryEntry, 18);
 221         OSMetaClassDeclareReservedUnused(IORegistryEntry, 19);
 222         OSMetaClassDeclareReservedUnused(IORegistryEntry, 20);
 223         OSMetaClassDeclareReservedUnused(IORegistryEntry, 21);
 224         OSMetaClassDeclareReservedUnused(IORegistryEntry, 22);
 225         OSMetaClassDeclareReservedUnused(IORegistryEntry, 23);
 226         OSMetaClassDeclareReservedUnused(IORegistryEntry, 24);
 227         OSMetaClassDeclareReservedUnused(IORegistryEntry, 25);
 228         OSMetaClassDeclareReservedUnused(IORegistryEntry, 26);
 229         OSMetaClassDeclareReservedUnused(IORegistryEntry, 27);
 230         OSMetaClassDeclareReservedUnused(IORegistryEntry, 28);
 231         OSMetaClassDeclareReservedUnused(IORegistryEntry, 29);
 232         OSMetaClassDeclareReservedUnused(IORegistryEntry, 30);
 233         OSMetaClassDeclareReservedUnused(IORegistryEntry, 31);
 234
 235 public:
 236
 237 /* Registry accessors */
 238
 239 /*! @function getRegistryRoot
 240  *   @abstract Returns a pointer to the root instance of the registry.
 241  *   @discussion This method provides an accessor to the root of the registry for the machine. The root may be passed to a registry iterator when iterating a plane, and contains properties that describe the available planes, and diagnostic information for IOKit. Keys for these properties are in IOKitKeys.h.
 242  *   @result A pointer to the IORegistryEntry root instance. It should not be released by the caller. */
 243
 244         static IORegistryEntry * getRegistryRoot( void );
 245
 246 /*! @function getGenerationCount
 247  *   @abstract Returns an generation count for all registry changing operations.
 248  *   @discussion This method provides an accessor to the current generation count (or seed) of the registry which changes when any topology change occurs in the registry - this does not include property table changes. It may be used to invalidate any caching of the results from IORegistryEntry methods.
 249  *   @result An integer generation count. */
 250
 251         static SInt32            getGenerationCount( void );
 252
 253 /*! @function getPlane
 254  *   @abstract Looks up the plane object by a C-string name.
 255  *   @discussion Planes are usually provided as globals by the creator, eg. gIOServicePlane, gIODeviceTreePlane, or gIOAudioPlane, however they may also be looked up by name with this method.
 256  *   @result A pointer to the plane object, or zero if no such plane exists. The returned plane should not be released. */
 257
 258         static const IORegistryPlane * getPlane( const char * name );
 259
 260 /* Registry Entry allocation & init */
 261
 262 /*! @function init
 263  *   @abstract Standard init method for all IORegistryEntry subclasses.
 264  *   @discussion A registry entry must be initialized with this method before it can be used. A property dictionary may passed and will be retained by this method for use as the registry entry's property table, or an empty one will be created.
 265  *   @param dictionary A dictionary that will become the registry entry's property table (retaining it), or zero which will cause an empty property table to be created.
 266  *   @result true on success, or false on a resource failure. */
 267
 268         virtual bool init( OSDictionary * dictionary = NULL );
 269
 270 /*! @function free
 271  *   @abstract Standard free method for all IORegistryEntry subclasses.
 272  *   @discussion This method will release any resources of the entry, in particular its property table. Note that the registry entry must always be detached from the registry before free may be called, and subclasses (namely IOService) will have additional protocols for removing registry entries. free should never need be called directly. */
 273
 274         virtual void free( void ) APPLE_KEXT_OVERRIDE;
 275
 276 /*! @function setPropertyTable
 277  *   @abstract Replace a registry entry's property table.
 278  *   @discussion This method will release the current property table of a the entry and replace it with another, retaining the new property table.
 279  *   @param dict The new dictionary to be used as the entry's property table. */
 280
 281         virtual void setPropertyTable( OSDictionary * dict );
 282
 283 /* Synchronized property accessors; wrappers to OSDictionary
 284  * plus property creation helpers */
 285
 286 /*! @function setProperty
 287  *   @abstract Synchronized method to add a property to a registry entry's property table.
 288  *   @discussion This method will add or replace a property in a registry entry's property table, using the OSDictionary::setObject semantics. This method is synchronized with other IORegistryEntry accesses to the property table.
 289  *   @param aKey The properties name as an OSSymbol.
 290  *   @param anObject The property value.
 291  *   @result true on success or false on a resource failure. */
 292
 293         virtual bool setProperty(const OSSymbol * aKey,
 294             OSObject * anObject);
 295
 296 #ifdef KERNEL_PRIVATE
 297         OSObject * setIndexedProperty(uint32_t index, OSObject * anObject);
 298         OSObject * getIndexedProperty(uint32_t index) const;
 299 #endif /* KERNEL_PRIVATE */
 300
 301 /*! @function setProperty
 302  *   @abstract Synchronized method to add a property to a registry entry's property table.
 303  *   @discussion This method will add or replace a property in a registry entry's property table, using the OSDictionary::setObject semantics. This method is synchronized with other IORegistryEntry accesses to the property table.
 304  *   @param aKey The property's name as an OSString.
 305  *   @param anObject The property value.
 306  *   @result true on success or false on a resource failure. */
 307
 308         virtual bool setProperty(const OSString * aKey, OSObject * anObject);
 309
 310 /*! @function setProperty
 311  *   @abstract Synchronized method to add a property to a registry entry's property table.
 312  *   @discussion This method will add or replace a property in a registry entry's property table, using the OSDictionary::setObject semantics. This method is synchronized with other IORegistryEntry accesses to the property table.
 313  *   @param aKey The property's name as a C-string.
 314  *   @param anObject The property value.
 315  *   @result true on success or false on a resource failure. */
 316
 317         virtual bool setProperty(const char * aKey, OSObject * anObject);
 318
 319 /*! @function setProperty
 320  *   @abstract Synchronized method to construct and add a OSString property to a registry entry's property table.
 321  *   @discussion This method will add or replace a property in a registry entry's property table, using the OSDictionary::setObject semantics. This method is synchronized with other IORegistryEntry accesses to the property table. The property is created as an OSString from the supplied C-string, set in the property table with the given name, and released.
 322  *   @param aKey The property's name as a C-string.
 323  *   @param aString The property value as a C-string.
 324  *   @result true on success or false on a resource failure. */
 325
 326         virtual bool setProperty(const char * aKey, const char * aString);
 327
 328 /*! @function setProperty
 329  *   @abstract Synchronized method to construct and add an OSBoolean property to a registry entry's property table.
 330  *   @discussion This method will add or replace a property in a registry entry's property table, using the OSDictionary::setObject semantics. This method is synchronized with other IORegistryEntry accesses to the property table. The property is created as an OSBoolean from the supplied value, set in the property table with the given name, and released.
 331  *   @param aKey The property's name as a C-string.
 332  *   @param aBoolean The property's boolean value.
 333  *   @result true on success or false on a resource failure. */
 334
 335         virtual bool setProperty(const char * aKey, bool aBoolean);
 336
 337 /*! @function setProperty
 338  *   @abstract Synchronized method to construct and add an OSNumber property to a registry entry's property table.
 339  *   @discussion This method will add or replace a property in a registry entry's property table, using the OSDictionary::setObject semantics. This method is synchronized with other IORegistryEntry accesses to the property table. The property is created as an OSNumber from the supplied value and size, set in the property table with the given name, and released.
 340  *   @param aKey The property's name as a C-string.
 341  *   @param aValue The property's numeric value.
 342  *   @param aNumberOfBits The property's size in bits, for OSNumber.
 343  *   @result true on success or false on a resource failure. */
 344
 345         virtual bool setProperty( const char *       aKey,
 346             unsigned long long aValue,
 347             unsigned int       aNumberOfBits);
 348
 349 /*! @function setProperty
 350  *   @abstract Synchronized method to construct and add an OSData property to a registry entry's property table.
 351  *   @discussion This method will add or replace a property in a registry entry's property table, using the OSDictionary::setObject semantics. This method is synchronized with other IORegistryEntry accesses to the property table. The property is created as an OSData copied from the supplied data and length, set in the property table with the given name, and released.
 352  *   @param aKey The property's name as a C-string.
 353  *   @param bytes The property's value as a pointer. OSData will copy this data.
 354  *   @param length The property's size in bytes, for OSData.
 355  *   @result true on success or false on a resource failure. */
 356
 357         virtual bool setProperty( const char *       aKey,
 358             void *             bytes,
 359             unsigned int       length);
 360
 361 /*! @function removeProperty
 362  *   @abstract Synchronized method to remove a property from a registry entry's property table.
 363  *   @discussion This method will remove a property from a registry entry's property table, using the OSDictionary::removeObject semantics. This method is synchronized with other IORegistryEntry accesses to the property table.
 364  *   @param aKey The property's name as an OSSymbol. */
 365
 366         virtual void removeProperty( const OSSymbol * aKey);
 367
 368 /*! @function removeProperty
 369  *   @abstract Synchronized method to remove a property from a registry entry's property table.
 370  *   @discussion This method will remove a property from a registry entry's property table, using the OSDictionary::removeObject semantics. This method is synchronized with other IORegistryEntry accesses to the property table.
 371  *   @param aKey The property's name as an OSString. */
 372
 373         virtual void removeProperty( const OSString * aKey);
 374
 375 /*! @function removeProperty
 376  *   @abstract Synchronized method to remove a property from a registry entry's property table.
 377  *   @discussion This method will remove a property from a registry entry's property table, using the OSDictionary::removeObject semantics. This method is synchronized with other IORegistryEntry accesses to the property table.
 378  *   @param aKey The property's name as a C-string. */
 379
 380         virtual void removeProperty( const char * aKey);
 381
 382 /*! @function getProperty
 383  *   @abstract Synchronized method to obtain a property from a registry entry's property table.
 384  *   @discussion This method will lookup a property in a registry entry's property table, using the OSDictionary::getObject semantics. This method is synchronized with other IORegistryEntry accesses to the property table.
 385  *   @param aKey The property's name as an OSSymbol.
 386  *   @result The property value found, or zero. */
 387
 388         virtual OSObject * getProperty( const OSSymbol * aKey) const;
 389
 390 /*! @function getProperty
 391  *   @abstract Synchronized method to obtain a property from a registry entry's property table.
 392  *   @discussion This method will lookup a property in a registry entry's property table, using the OSDictionary::getObject semantics. This method is synchronized with other IORegistryEntry accesses to the property table.
 393  *   @param aKey The property's name as an OSString.
 394  *   @result The property value found, or zero. */
 395
 396         virtual OSObject * getProperty( const OSString * aKey) const;
 397
 398 /*! @function getProperty
 399  *   @abstract Synchronized method to obtain a property from a registry entry's property table.
 400  *   @discussion This method will lookup a property in a registry entry's property table, using the OSDictionary::getObject semantics. This method is synchronized with other IORegistryEntry accesses to the property table.
 401  *   @param aKey The property's name as a C-string.
 402  *   @result The property value found, or zero. */
 403
 404         virtual OSObject * getProperty( const char * aKey) const;
 405
 406 /*! @function getProperty
 407  *   @abstract Synchronized method to obtain a property from a registry entry or one of its parents (or children) in the hierarchy.
 408  *   @discussion This method will search for a property, starting first with this registry entry's property table, then iterating recusively through either the parent registry entries or the child registry entries of this entry. Once the first occurrence is found, it will lookup and return the value of the property, using the OSDictionary::getObject semantics. The iteration keeps track of entries that have been recursed into previously to avoid loops. This method is synchronized with other IORegistryEntry accesses to the property table(s).
 409  *   @param aKey The property's name as an OSSymbol.
 410  *   @param plane The plane to iterate over, eg. gIOServicePlane.
 411  *   @param options kIORegistryIterateRecursively may be set to recurse automatically into the registry hierarchy. Without this option, this method degenerates into the standard getProperty() call. kIORegistryIterateParents may be set to iterate the parents of the entry, in place of the children.
 412  *   @result The property value found, or zero. */
 413
 414         virtual OSObject * getProperty( const OSSymbol *        aKey,
 415             const IORegistryPlane * plane,
 416             IOOptionBits            options =
 417             kIORegistryIterateRecursively |
 418             kIORegistryIterateParents) const;
 419
 420 /*! @function getProperty
 421  *   @abstract Synchronized method to obtain a property from a registry entry or one of its parents (or children) in the hierarchy.
 422  *   @discussion This method will search for a property, starting first with this registry entry's property table, then iterating recusively through either the parent registry entries or the child registry entries of this entry. Once the first occurrence is found, it will lookup and return the value of the property, using the OSDictionary::getObject semantics. The iteration keeps track of entries that have been recursed into previously to avoid loops. This method is synchronized with other IORegistryEntry accesses to the property table(s).
 423  *   @param aKey The property's name as an OSString.
 424  *   @param plane The plane to iterate over, eg. gIOServicePlane.
 425  *   @param options kIORegistryIterateRecursively may be set to recurse automatically into the registry hierarchy. Without this option, this method degenerates into the standard getProperty() call. kIORegistryIterateParents may be set to iterate the parents of the entry, in place of the children.
 426  *   @result The property value found, or zero. */
 427
 428         virtual OSObject * getProperty( const OSString *        aKey,
 429             const IORegistryPlane * plane,
 430             IOOptionBits            options =
 431             kIORegistryIterateRecursively |
 432             kIORegistryIterateParents) const;
 433
 434 /*! @function getProperty
 435  *   @abstract Synchronized method to obtain a property from a registry entry or one of its parents (or children) in the hierarchy.
 436  *   @discussion This method will search for a property, starting first with this registry entry's property table, then iterating recusively through either the parent registry entries or the child registry entries of this entry. Once the first occurrence is found, it will lookup and return the value of the property, using the OSDictionary::getObject semantics. The iteration keeps track of entries that have been recursed into previously to avoid loops. This method is synchronized with other IORegistryEntry accesses to the property table(s).
 437  *   @param aKey The property's name as a C-string.
 438  *   @param plane The plane to iterate over, eg. gIOServicePlane.
 439  *   @param options kIORegistryIterateRecursively may be set to recurse automatically into the registry hierarchy. Without this option, this method degenerates into the standard getProperty() call. kIORegistryIterateParents may be set to iterate the parents of the entry, in place of the children.
 440  *   @result The property value found, or zero. */
 441
 442         virtual OSObject * getProperty( const char *            aKey,
 443             const IORegistryPlane * plane,
 444             IOOptionBits            options =
 445             kIORegistryIterateRecursively |
 446             kIORegistryIterateParents) const;
 447
 448 /*! @function copyProperty
 449  *   @abstract Synchronized method to obtain a property from a registry entry's property table.
 450  *   @discussion This method will lookup a property in a registry entry's property table, using the OSDictionary::getObject semantics, and return a reference to the caller. This method is synchronized with other IORegistryEntry accesses to the property table.
 451  *   @param aKey The property's name as an OSSymbol.
 452  *   @result The property value found, or zero. It should be released by the caller. */
 453
 454         virtual OSObject * copyProperty( const OSSymbol * aKey) const;
 455
 456 /*! @function copyProperty
 457  *   @abstract Synchronized method to obtain a property from a registry entry's property table.
 458  *   @discussion This method will lookup a property in a registry entry's property table, using the OSDictionary::getObject semantics, and return a reference to the caller. This method is synchronized with other IORegistryEntry accesses to the property table.
 459  *   @param aKey The property's name as an OSString.
 460  *   @result The property value found, or zero. It should be released by the caller. */
 461
 462         virtual OSObject * copyProperty( const OSString * aKey) const;
 463
 464 /*! @function copyProperty
 465  *   @abstract Synchronized method to obtain a property from a registry entry's property table.
 466  *   @discussion This method will lookup a property in a registry entry's property table, using the OSDictionary::getObject semantics, and return a reference to the caller. This method is synchronized with other IORegistryEntry accesses to the property table.
 467  *   @param aKey The property's name as a C-string.
 468  *   @result The property value found, or zero. It should be released by the caller. */
 469
 470         virtual OSObject * copyProperty( const char * aKey) const;
 471
 472 /*! @function dictionaryWithProperties
 473  *   @abstract Synchronized method to obtain copy a registry entry's property table.
 474  *   @discussion This method will copy a registry entry's property table, using the OSDictionary::withDictionary semantics. This method is synchronized with other IORegistryEntry accesses to the property table. Since OSDictionary will only copy property values by reference, synchronization is not guaranteed to any collection values.
 475  *   @result The created dictionary, or zero on a resource value. It should be released by the caller. */
 476
 477         virtual OSDictionary * dictionaryWithProperties( void ) const;
 478
 479 /*! @function serializeProperties
 480  *   @abstract Synchronized method to serialize a registry entry's property table.
 481  *   @discussion This method will serialize a registry entry's property table, using the OSDictionary::serialize semantics. This method is synchronized with other IORegistryEntry accesses to the property table. Many non-kernel clients of IOKit read information from the registry via properties, and will invoke this method in a registry entry to create a serialization of all the entry's properties, which is then reconstructed in the client's task as a CFDictionary. This method may be intercepted by subclasses to update their properties or implement a different serialization method, though it is usually better to implement such functionality by creating objects in the property table and implementing their serialize methods, avoiding any need to implement serializeProperties.
 482  *   @param serialize The OSSerialize instance representing the serialization request.
 483  *   @result True on success, false otherwise. */
 484
 485         virtual bool serializeProperties( OSSerialize * serialize ) const;
 486
 487 /* Unsynchronized(!) property table access */
 488
 489 /*! @function getPropertyTable
 490  *   @abstract Unsynchronized accessor to a registry entry's property table.
 491  *   @discussion This method will return a pointer to the live property table as an OSDictionery. Its use is not recommended in most cases, instead use the synchronized accessors and helper functions of IORegistryEntry to access properties. It can only safely be used by one thread, which usually means it can only be used before a registry entry is entered into the registry.
 492  *   @result A pointer to the property table as an OSDictionary. The pointer is valid while the registry entry is retained, and should not be released by the caller. */
 493
 494 /* inline */ OSDictionary * getPropertyTable( void ) const;
 495 /* { return(fPropertyTable); } */
 496
 497 /* Set properties from user level, to be overridden if supported */
 498
 499 /*! @function setProperties
 500  *   @abstract Optionally supported external method to set properties in a registry entry.
 501  *   @discussion This method is not implemented by IORegistryEntry, but is available to kernel and non-kernel clients to set properties in a registry entry. IOUserClient provides connection based, more controlled access to this functionality and may be more appropriate for many uses, since there is no differentiation between clients available to this method.
 502  *   @param properties Any OSObject subclass, to be interpreted by the implementing method - for example an OSDictionary, OSData etc. may all be appropriate.
 503  *   @result An IOReturn code to be returned to the caller. */
 504
 505         virtual IOReturn setProperties( OSObject * properties );
 506
 507 /* Topology */
 508
 509 /*! @function getParentIterator
 510  *   @abstract Returns an iterator over an registry entry's parent entries in a specified plane.
 511  *   @param plane The plane object.
 512  *   @result Returns an iterator over the parents of the registry entry, or zero if there is a resource failure. The iterator must be released when the iteration is finished. All objects returned by the iteration are retained while the iterator is valid, though they may no longer be attached during the iteration. */
 513
 514         virtual OSIterator * getParentIterator( const IORegistryPlane * plane )
 515         const;
 516         virtual void applyToParents( IORegistryEntryApplierFunction applier,
 517             void * context,
 518             const IORegistryPlane * plane ) const;
 519
 520 /*! @function getParentEntry
 521  *   @abstract Returns an registry entry's first parent entry in a plane.
 522  *   @discussion This function will return the parent to which a registry entry was first attached. Since the majority of registry entrys have only one provider, this is a useful simplification.
 523  *   @param plane The plane object.
 524  *   @result Returns the first parent of the registry entry, or zero if the entry is not attached into the registry in that plane. The parent is retained while the entry is attached, and should not be released by the caller. */
 525
 526         virtual IORegistryEntry * getParentEntry( const IORegistryPlane * plane ) const;
 527
 528 /*! @function getChildIterator
 529  *   @abstract Returns an iterator over an registry entry's child entries in a plane.
 530  *   @discussion This method creates an iterator which will return each of a registry entry's child entries in a specified plane.
 531  *   @param plane The plane object.
 532  *   @result Returns an iterator over the children of the entry, or zero if there is a resource failure. The iterator must be released when the iteration is finished. All objects returned by the iteration are retained while the iterator is valid, though they may no longer be attached during the iteration. */
 533
 534         virtual OSIterator * getChildIterator( const IORegistryPlane * plane )
 535         const;
 536
 537 #if XNU_KERNEL_PRIVATE
 538         uint32_t getChildCount( const IORegistryPlane * plane ) const;
 539         OSArray * copyPropertyKeys(void) const;
 540 #endif
 541
 542         virtual void applyToChildren( IORegistryEntryApplierFunction applier,
 543             void * context,
 544             const IORegistryPlane * plane ) const;
 545
 546 /*! @function getChildEntry
 547  *   @abstract Returns an registry entry's first child entry in a plane.
 548  *   @discussion This function will return the child which first attached to a registry entry.
 549  *   @param plane The plane object.
 550  *   @result Returns the first child of the registry entry, or zero if the entry is not attached into the registry in that plane. The child is retained while the entry is attached, and should not be released by the caller. */
 551
 552         virtual IORegistryEntry * getChildEntry( const IORegistryPlane * plane ) const;
 553
 554 /*! @function isChild
 555  *   @abstract Determines whether a registry entry is the child of another in a plane.
 556  *   @discussion This method called in the parent entry determines if the specified entry is a child, in a plane. Additionally, it can check if the child is the only child of the parent entry.
 557  *   @param child The possible child registry entry.
 558  *   @param plane The plane object.
 559  *   @param onlyChild If true, check also if the child is the only child.
 560  *   @result If the child argument is not a child of the registry entry, false is returned. If onlyChild is true and the child is not the only child of the entry, false is returned, otherwise true is returned. */
 561
 562         virtual bool isChild( IORegistryEntry * child,
 563             const IORegistryPlane * plane,
 564             bool onlyChild = false ) const;
 565
 566 /*! @function isParent
 567  *   @abstract Determines whether a registry entry is the parent of another in a plane.
 568  *   @discussion This method called in the child entry determines if the specified entry is a parent, in a plane. Additionally, it can check if the parent is the only parent of the child entry.
 569  *   @param parent The possible parent registry entry.
 570  *   @param plane The plane object.
 571  *   @param onlyParent If true, check also if the parent is the only parent.
 572  *   @result If the parent argument is not a parent of the registry entry, false is returned. If onlyParent is true and the parent is not the only parent of the entry, false is returned, otherwise true is returned. */
 573
 574         virtual bool isParent( IORegistryEntry * parent,
 575             const IORegistryPlane * plane,
 576             bool onlyParent = false ) const;
 577
 578 /*! @function inPlane
 579  *   @abstract Determines whether a registry entry is attached in a plane.
 580  *   @discussion This method determines if the entry is attached in a plane to any other entry.  It can also be used to determine if the entry is a member of any plane.
 581  *   @param plane The plane object, 0 indicates any plane.
 582  *   @result If the entry has a parent in the given plane or if plane = 0 then if entry has any parent; return true, otherwise false. */
 583
 584         virtual bool inPlane( const IORegistryPlane * plane = NULL) const;
 585
 586 /*! @function getDepth
 587  *   @abstract Counts the maximum number of entries between an entry and the registry root, in a plane.
 588  *   @discussion This method counts the number of entries between and entry and the registry root, in a plane, for each parent of the entry and returns the maximum value.
 589  *   @param plane The plane object.
 590  *   @result The maximum number of entries between the entry and the root. Zero is returned if the entry is not attached in the plane. */
 591
 592         virtual unsigned int getDepth( const IORegistryPlane * plane ) const;
 593
 594 /* Attach / detach */
 595
 596 /*! @function attachToParent
 597  *   @abstract Attaches a entry to a parent entry in a plane.
 598  *   @discussion This is the usual method of entering an entry into the registry. It is a no-op and success if the entry is already attached to the parent. Attaching the  entry into the registry retains both the child and parent while they are attached. This method will call attachToChild in the parent entry if it is not being called from attachToChild.
 599  *   @param parent The registry entry to attach to.
 600  *   @param plane The plane object.
 601  *   @result true on success, or false on a resource failure, or if the parent is the same as the child. */
 602
 603         virtual bool attachToParent( IORegistryEntry * parent,
 604             const IORegistryPlane * plane );
 605
 606 /*! @function detachFromParent
 607  *   @abstract Detaches an entry from a parent entry in a plane.
 608  *   @discussion This is the usual method of removing an entry from the registry. It is a no-op if the entry is not attached to the parent. Detaching the entry will release both the child and parent. This method will call detachFromChild in the parent entry if it is not being called from detachFromChild.
 609  *   @param parent The registry entry to detach from.
 610  *   @param plane The plane object. */
 611
 612         virtual void detachFromParent( IORegistryEntry * parent,
 613             const IORegistryPlane * plane );
 614
 615 /*! @function attachToChild
 616  *   @abstract Method called in the parent entry when a child attaches.
 617  *   @discussion This method is called in the parent entry when a child attaches, to make overrides possible. This method will also call attachToParent in the child entry if it is not being called from attachToParent. It is a no-op and success if the entry is already a child. Attaching the  entry into the registry retains both the child and parent while they are attached.
 618  *   @param child The registry entry being attached.
 619  *   @param plane The plane object.
 620  *   @result true on success, or false on a resource failure, or if the parent is the same as the child. */
 621
 622         virtual bool attachToChild( IORegistryEntry * child,
 623             const IORegistryPlane * plane );
 624
 625 /*! @function detachFromChild
 626  *   @abstract Detaches a child entry from its parent in a plane.
 627  *   @discussion This method is called in the parent entry when a child detaches, to make overrides possible. It is a no-op if the entry is not a child of the parent. Detaching the entry will release both the child and parent. This method will call detachFromParent in the child entry if it is not being called from detachFromParent.
 628  *   @param child The registry entry to detach.
 629  *   @param plane The plane object. */
 630
 631         virtual void detachFromChild( IORegistryEntry * child,
 632             const IORegistryPlane * plane );
 633
 634 /*! @function detachAbove
 635  *   @abstract Detaches an entry from all its parent entries in a plane.
 636  *   @discussion This method calls detachFromParent in the entry for each of its parent entries in the plane.
 637  *   @param plane The plane object. */
 638
 639         virtual void detachAbove( const IORegistryPlane * plane );
 640
 641 /*! @function detachAll
 642  *   @abstract Detaches an entry and all its children recursively in a plane.
 643  *   @discussion This method breaks the registry connections for a subtree. detachAbove is called in the entry, and all child entries and their children in the plane.
 644  *   @param plane The plane object. */
 645
 646         virtual void detachAll( const IORegistryPlane * plane );
 647
 648 /* Name, location and path accessors */
 649
 650 /*! @function getName
 651  *   @abstract Returns the name assigned to the registry entry as a C-string.
 652  *   @discussion Entries can be named in a particular plane, or globally. If the entry is named in plane and the plane is specified that name will be returned, otherwise the global name is returned. The global name defaults to the entry's meta class name if it has not been named.
 653  *   @param plane The plane object, or zero for the global name.
 654  *   @result A C-string name, valid while the entry is retained. */
 655
 656         virtual const char * getName( const IORegistryPlane * plane = NULL ) const;
 657
 658 /*! @function copyName
 659  *   @abstract Returns the name assigned to the registry entry as an OSSymbol.
 660  *   @discussion Entries can be named in a particular plane, or globally. If the entry is named in plane and the plane is specified that name will be returned, otherwise the global name is returned. The global name defaults to the entry's meta class name if it has not been named.
 661  *   @param plane The plane object, or zero for the global name.
 662  *   @result A reference to an OSSymbol for the name, which should be released by the caller. */
 663
 664         virtual const OSSymbol * copyName(
 665                 const IORegistryPlane * plane = NULL ) const;
 666
 667 /*! @function compareNames
 668  *   @abstract Compares the name of the entry with one or more names, and optionally returns the matching name.
 669  *   @discussion This method is called during IOService name matching and elsewhere to compare the entry's global name with a list of names, or a single name. A list of names may be passed as any OSCollection of OSStrings, while a single name may be passed an OSString, in the name parameter. compareNames will call the compareName method for each name, for overrides.
 670  *   @param name The name or names to compare with as any OSCollection (eg. OSArray, OSSet, OSDictionary) of OSStrings, or a single name may be passed an OSString.
 671  *   @param matched If the caller wants the successfully matched name returned, pass a non-zero pointer for the matched parameter and an OSString will be returned here. It should be released by the caller.
 672  *   @result True if one of the names compared true with the entry's global name. */
 673
 674         virtual bool compareNames( OSObject * name, OSString ** matched = NULL ) const;
 675
 676 /*! @function compareName
 677  *   @abstract Compares the name of the entry with one name, and optionally returns the matching name.
 678  *   @discussion This method is called during IOService name matching and elsewhere from the compareNames method. It should be overridden to provide non-standard name matching.
 679  *   @param name The name to compare with as an OSString.
 680  *   @param matched If the caller wants the successfully matched name returned, pass a non-zero pointer for the matched parameter and an OSString will be returned here. It should be released by the caller. Generally, this will be the same as the name parameter, but may not be if wildcards are used.
 681  *   @result True if the name compared true with the entry's global name. */
 682
 683         virtual bool compareName( OSString * name, OSString ** matched = NULL ) const;
 684
 685 /*! @function setName
 686  *   @abstract Sets a name for the registry entry, in a particular plane, or globally.
 687  *   @discussion Entries can be named in a particular plane, or globally. If the plane is specified the name applies only to that plane, otherwise the global name is set. The global name defaults to the entry's meta class name if it has not been named.
 688  *   @param name An OSSymbol which will be retained.
 689  *   @param plane The plane object, or zero to set the global name. */
 690
 691         virtual void setName( const OSSymbol * name,
 692             const IORegistryPlane * plane = NULL );
 693
 694 /*! @function setName
 695  *   @abstract Sets a name for the registry entry, in a particular plane, or globally.
 696  *   @discussion Entries can be named in a particular plane, or globally. If the plane is specified the name applies only to that plane, otherwise the global name is set. The global name defaults to the entry's meta class name if it has not been named.
 697  *   @param name A const C-string name which will be copied.
 698  *   @param plane The plane object, or zero to set the global name. */
 699
 700         virtual void setName( const char * name,
 701             const IORegistryPlane * plane = NULL );
 702
 703 /*! @function getLocation
 704  *   @abstract Returns the location string assigned to the registry entry as a C-string.
 705  *   @discussion Entries can given a location string in a particular plane, or globally. If the entry has had a location set in a plane and the plane is specified that location string will be returned, otherwise the global location string is returned. If no global location string has been set, zero is returned.
 706  *   @param plane The plane object, or zero for the global name.
 707  *   @result A C-string location string, valid while the entry is retained, or zero. */
 708
 709         virtual const char * getLocation( const IORegistryPlane * plane = NULL ) const;
 710
 711 /*! @function copyLocation
 712  *   @abstract Returns the location string assigned to the registry entry as an OSSymbol.
 713  *   @discussion Entries can given a location string in a particular plane, or globally. If the entry has had a location set in a plane and the plane is specified that location string will be returned, otherwise the global location string is returned. If no global location string has been set, zero is returned.
 714  *   @param plane The plane object, or zero for the global name.
 715  *   @result A reference to an OSSymbol for the location if one exists, which should be released by the caller, or zero. */
 716
 717         virtual const OSSymbol * copyLocation(
 718                 const IORegistryPlane * plane = NULL ) const;
 719
 720 /*! @function setLocation
 721  *   @abstract Sets a location string for the registry entry, in a particular plane, or globally.
 722  *   @discussion Entries can be given a location string in a particular plane, or globally. If the plane is specified the location applies only to that plane, otherwise the global location is set. The location string may be used during path lookups of registry entries, to distinguish between sibling entries with the same name. The default IORegistryEntry parsing of location strings expects a list of hex numbers separated by commas, though subclasses of IORegistryEntry might do their own parsing.
 723  *   @param location A C-string location string which will be copied, or an OSSymbol which will be retained.
 724  *   @param plane The plane object, or zero to set the global location string. */
 725
 726         virtual void setLocation( const OSSymbol * location,
 727             const IORegistryPlane * plane = NULL );
 728         virtual void setLocation( const char * location,
 729             const IORegistryPlane * plane = NULL );
 730
 731 /*! @function getPath
 732  *   @abstract Create a path for a registry entry.
 733  *   @discussion The path for a registry entry is copied to the caller's buffer. The path describes the entry's attachment in a particular plane, which must be specified. The path begins with the plane name followed by a colon, and then followed by '/' separated path components for each of the entries between the root and the registry entry. Each component is constructed with the getPathComponent method called in each entry. An alias may also exist for the entry, which are described as properties in a registry entry found at /aliases in the plane. If a property value interpreted as a path in a call to IORegistryEntry::fromPath yields the entry, then the property name is used as the entry's path.
 734  *   @param path A char buffer allocated by the caller.
 735  *   @param length An in/out parameter - the caller sets the length of the buffer available, and getPath returns the total length of the path copied to the buffer.
 736  *   @param plane The plane object.
 737  *   @result getPath will fail if the entry is not attached in the plane, or if the buffer is not large enough to contain the path. */
 738
 739         virtual bool getPath( char * path, int * length,
 740             const IORegistryPlane * plane) const;
 741
 742 /*! @function getPathComponent
 743  *   @abstract Create a path component for a registry entry.
 744  *   @discussion Each component of a path created with getPath is created with getPathComponent. The default implementation concatenates the entry's name in the the plane, with the "at" symbol and the location string of the entry in the plane if it has been set.
 745  *   @param path A char buffer allocated by the caller.
 746  *   @param length An in/out parameter - the caller sets the length of the buffer available, and getPathComponent returns the total length of the path component copied to the buffer.
 747  *   @param plane The plane object.
 748  *   @result true if the path fits into the supplied buffer or false on a overflow. */
 749
 750         virtual bool getPathComponent( char * path, int * length,
 751             const IORegistryPlane * plane ) const;
 752
 753 /*! @function fromPath
 754  *   @abstract Looks up a registry entry by path.
 755  *   @discussion This function parses paths to lookup registry entries. The path may begin with the <plane name>: created by getPath, or the plane may be set by the caller. If there are characters remaining unparsed after an entry has been looked up, this may be considered an invalid lookup, or those characters may be passed back to the caller and the lookup successful.
 756  *   @param path A C-string path.
 757  *   @param plane The plane to lookup up the path, or zero, in which case the path must begin with the plane name.
 758  *   @param residualPath If the path may contain residual characters after the last path component, the residual will be copied back to the caller's residualPath buffer. If there are residual characters and no residual buffer is specified, fromPath will fail.
 759  *   @param residualLength An in/out parameter - the caller sets the length of the residual buffer available, and fromPath returns the total length of the residual path copied to the buffer. If there is no residualBuffer (residualPath = 0) then residualLength may be zero also.
 760  *   @param fromEntry The lookup will proceed rooted at this entry if non-zero, otherwise it proceeds from the root of the plane.
 761  *   @result A retained registry entry is returned on success, or zero on failure. The caller should release the entry. */
 762
 763         static IORegistryEntry * fromPath(  const char * path,
 764             const IORegistryPlane * plane = NULL,
 765             char * residualPath = NULL,
 766             int * residualLength = NULL,
 767             IORegistryEntry * fromEntry = NULL );
 768
 769 /*! @function fromPath
 770  *   @abstract Looks up a registry entry by relative path.
 771  *   @discussion This function looks up a entry below the called entry by a relative path. It is just a convenience that calls IORegistryEntry::fromPath with this as the fromEntry parameter.
 772  *   @param path See IORegistryEntry::fromPath.
 773  *   @param plane See IORegistryEntry::fromPath.
 774  *   @param residualPath See IORegistryEntry::fromPath.
 775  *   @param residualLength See IORegistryEntry::fromPath.
 776  *   @result See IORegistryEntry::fromPath. */
 777
 778         virtual IORegistryEntry * childFromPath( const char * path,
 779             const IORegistryPlane * plane = NULL,
 780             char * residualPath = NULL,
 781             int * residualLength = NULL );
 782
 783 /*! @function dealiasPath
 784  *   @abstract Strips any aliases from the head of path and returns the full path.
 785  *   @discussion If the path specified begins with an alias found in the /aliases entry, the value of the alias is returned, and a pointer into the passed in path after the alias is passed back to the caller. If an alias is not found, zero is returned and the path parameter is unchanged.
 786  *   @param opath An in/out paramter - the caller passes in a pointer to a C-string pointer to a path. If an alias is found, dealiasPath returns a pointer into the path just beyond the end of the alias.
 787  *   @param plane A plane object must be specified.
 788  *   @result A C-string pointer to the value of the alias if one is found, or zero if not. */
 789
 790         static const char * dealiasPath( const char ** opath,
 791             const IORegistryPlane * plane );
 792
 793 /*! @function makePlane
 794  *   @abstract Constructs an IORegistryPlane object.
 795  *   @discussion Most planes in IOKit are created by the OS, although other planes may be created.
 796  *   @param name A C-string name for the new plane, to be copied.
 797  *   @result A new instance of an IORegistryPlane, or zero on failure. */
 798
 799         static const IORegistryPlane * makePlane( const char * name );
 800
 801 /*!    @abstract Returns an ID for the registry entry that is global to all tasks.
 802  *   @discussion The entry ID returned by getRegistryEntryID can be used to identify a registry entry across all tasks. A registry entry may be looked up by its entry ID by creating a matching dictionary with IORegistryEntryIDMatching() in user space, or <code>IOService::registryEntryIDMatching()</code> in the kernel, to be used with the IOKit matching functions. The ID is valid only until the machine reboots.
 803  *   @result An ID for the registry entry, assigned when the entry is first attached in the registry. */
 804
 805         uint64_t getRegistryEntryID( void );
 806
 807 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 808 /* * * * * * * * * * * * internals * * * * * * * * * * * */
 809 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 810
 811         virtual bool init( IORegistryEntry * from,
 812             const IORegistryPlane * inPlane );
 813
 814 #ifdef XNU_KERNEL_PRIVATE
 815 public:
 816 #else
 817 private:
 818 #endif
 819         static LIBKERN_RETURNS_NOT_RETAINED IORegistryEntry * initialize( void );
 820
 821 #ifdef XNU_KERNEL_PRIVATE
 822         SInt32 getRegistryEntryGenerationCount( void ) const;
 823         void setName(const OSString * name,
 824             const IORegistryPlane * plane = NULL);
 825 #endif
 826
 827 private:
 828         inline bool arrayMember( OSArray * set,
 829             const IORegistryEntry * member,
 830             unsigned int * index = NULL ) const;
 831
 832         bool makeLink( IORegistryEntry * to,
 833             unsigned int relation,
 834             const IORegistryPlane * plane ) const;
 835         void breakLink( IORegistryEntry * to,
 836             unsigned int relation,
 837             const IORegistryPlane * plane ) const;
 838
 839         APPLE_KEXT_COMPATIBILITY_VIRTUAL
 840         OSArray * getParentSetReference( const IORegistryPlane * plane )
 841         const;
 842
 843         APPLE_KEXT_COMPATIBILITY_VIRTUAL
 844         OSArray * getChildSetReference( const IORegistryPlane * plane )
 845         const;
 846
 847         APPLE_KEXT_COMPATIBILITY_VIRTUAL
 848         IORegistryEntry * getChildFromComponent( const char ** path,
 849             const IORegistryPlane * plane );
 850
 851         APPLE_KEXT_COMPATIBILITY_VIRTUAL
 852         LIBKERN_RETURNS_NOT_RETAINED const OSSymbol * hasAlias(
 853                 const IORegistryPlane * plane,
 854                 char * opath = NULL, int * length = NULL ) const;
 855
 856         APPLE_KEXT_COMPATIBILITY_VIRTUAL
 857         const char * matchPathLocation( const char * cmp,
 858             const IORegistryPlane * plane );
 859 };
 860
 861 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 862
 863 /*! @class IORegistryIterator : public OSIterator
 864  *   @abstract An iterator over the registry.
 865  *   @discussion An iterator that can traverse the children or parents of a registry entry in a plane, and recurse. Access to the registry is protected against multiple threads, but an IORegistryIterator instance is for use by one thread only. */
 866
 867 class IORegistryIterator : public OSIterator
 868 {
 869         OSDeclareAbstractStructors(IORegistryIterator);
 870
 871 private:
 872         struct IORegCursor {
 873                 IORegCursor          *  next;
 874                 IORegistryEntry      *  current;
 875                 OSIterator           *  iter;
 876         };
 877         IORegCursor                 start;
 878         IORegCursor           *     where;
 879         IORegistryEntry       *     root;
 880         OSOrderedSet          *     done;
 881         const IORegistryPlane *     plane;
 882         IOOptionBits                options;
 883
 884         virtual void free( void ) APPLE_KEXT_OVERRIDE;
 885
 886 public:
 887 /*! @function iterateOver
 888  *   @abstract Create an iterator rooted at a given registry entry.
 889  *   @discussion This method creates an IORegistryIterator that is set up with options to iterate children or parents of a root entry, and to recurse automatically into entries as they are returned, or only when instructed. The iterator object keeps track of entries that have been recursed into previously to avoid loops.
 890  *   @param start The root entry to begin the iteration at.
 891  *   @param plane A plane object must be specified.
 892  *   @param options kIORegistryIterateRecursively may be set to recurse automatically into each entry as it is returned. This option affects the behaviour of the getNextObject method, which is defined in the OSIterator superclass. Other methods will override this behaviour. kIORegistryIterateParents may be set to iterate the parents of each entry, by default the children are iterated.
 893  *   @result A created IORegistryIterator instance, to be released by the caller when it has finished with it. */
 894
 895         static IORegistryIterator * iterateOver( IORegistryEntry * start,
 896             const IORegistryPlane * plane,
 897             IOOptionBits options = 0 );
 898
 899 /*! @function iterateOver
 900  *   @abstract Create an iterator rooted at the registry root.
 901  *   @discussion This method creates an IORegistryIterator that is set up with options to iterate children of the registry root entry, and to recurse automatically into entries as they are returned, or only when instructed. The iterator object keeps track of entries that have been recursed into previously to avoid loops.
 902  *   @param plane A plane object must be specified.
 903  *   @param options kIORegistryIterateRecursively may be set to recurse automatically into each entry as it is returned. This option affects the behaviour of the getNextObject method, which is defined in the OSIterator superclass. Other methods will override this behaviour. kIORegistryIterateParents may be set to iterate the parents of each entry, by default the children are iterated.
 904  *   @result A created IORegistryIterator instance, to be released by the caller when it has finished with it. */
 905
 906         static IORegistryIterator * iterateOver( const IORegistryPlane * plane,
 907             IOOptionBits options = 0 );
 908
 909 /*! @function getNextObject
 910  *   @abstract Return the next object in the registry iteration.
 911  *   @discussion This method calls either getNextObjectFlat or getNextObjectRecursive depending on the options the iterator was created with. This implements the OSIterator defined getNextObject method. The object returned is retained while the iterator is pointing at it (its the current entry), or recursing into it. The caller should not release it.
 912  *   @result The next registry entry in the iteration (the current entry), or zero if the iteration has finished at this level of recursion. The entry returned is retained while the iterator is pointing at it (its the current entry), or recursing into it. The caller should not release it. */
 913
 914         virtual IORegistryEntry * getNextObject( void ) APPLE_KEXT_OVERRIDE;
 915
 916 /*! @function getNextObjectFlat
 917  *   @abstract Return the next object in the registry iteration, ignoring the kIORegistryIterateRecursively option.
 918  *   @discussion This method returns the next child, or parent if the kIORegistryIterateParents option was used to create the iterator, of the current root entry. The object returned is retained while the iterator is pointing at it (its the current entry), or recursing into it. The caller should not release it.
 919  *   @result The next registry entry in the iteration (the current entry), or zero if the iteration has finished at this level of recursion, or the iteration is invalid (see isValid). The entry returned is retained while the iterator is pointing at it (its the current entry), or recursing into it. The caller should not release it. */
 920
 921         virtual IORegistryEntry * getNextObjectFlat( void );
 922
 923 /*! @function getNextObjectRecursive
 924  *   @abstract Return the next object in the registry iteration, and enter it.
 925  *   @discussion If the iterator has a current entry, and the iterator has not already entered previously, enterEntry is called to recurse into it, ie. make it the new root, and the next child, or parent if the kIORegistryIterateParents option was used to create the iterator, at this new level of recursion is returned. If there is no current entry at this level of recursion, exitEntry is called and the process repeats, until the iteration returns to the entry the iterator was created with and zero is returned. The object returned is retained while the iterator is pointing at it (its the current entry), or recursing into it. The caller should not release it.
 926  *   @result The next registry entry in the iteration (the current entry), or zero if its finished, or the iteration is invalid (see isValid). The entry returned is retained while the iterator is pointing at it (its the current entry), or recursing into it. The caller should not release it. */
 927
 928         virtual IORegistryEntry * getNextObjectRecursive( void );
 929
 930 /*! @function getCurrentEntry
 931  *   @abstract Return the current entry in the registry iteration.
 932  *   @discussion This method returns the current entry, last returned by getNextObject et al. The object returned is retained while the iterator is pointing at it (its the current entry), or recursing into it. The caller should not release it. If the iteration is no longer valid (see isValid), the current entry is zero.
 933  *   @result The current registry entry in the iteration, or zero if the last iteration returned zero, or the iteration is invalid (see isValid). The entry returned is retained while the iterator is pointing at it (its the current entry), or recursing into it. The caller should not release it. */
 934
 935         virtual IORegistryEntry * getCurrentEntry( void );
 936
 937 /*! @function enterEntry
 938  *   @abstract Recurse into the current entry in the registry iteration.
 939  *   @discussion This method makes the current entry, ie. the last entry returned by getNextObject et al., the root in a new level of recursion. */
 940
 941         virtual void enterEntry( void );
 942
 943 /*! @function enterEntry
 944  *   @abstract Recurse into the current entry in the registry iteration.
 945  *   @discussion This method recurses into an entry as with enterEntry, but also switches from the current plane to a new one set by the caller.
 946  *   @param plane The new plane to switch into. */
 947
 948         virtual void enterEntry( const IORegistryPlane * plane );
 949
 950 /*! @function exitEntry
 951  *   @abstract Exits a level of recursion, restoring the current entry.
 952  *   @discussion This method undoes an enterEntry, restoring the current entry. If there are no more levels of recursion to exit false is returned, otherwise true is returned.
 953  *   @result true if a level of recursion was undone, false if no recursive levels are left in the iteration. */
 954
 955         virtual bool exitEntry( void );
 956
 957 /*! @function reset
 958  *   @abstract Exits all levels of recursion, restoring the iterator to its state at creation.
 959  *   @discussion This method exits all levels of recursion, and restores the iterator to its state at creation. */
 960
 961         virtual void reset( void ) APPLE_KEXT_OVERRIDE;
 962
 963 /*! @function isValid
 964  *   @abstract Checks that no registry changes have invalidated the iteration.
 965  *   @discussion If a registry iteration is invalidated by changes to the registry, it will be made invalid, the currentEntry will be considered zero, and further calls to getNextObject et al. will return zero. The iterator should be reset to restart the iteration when this happens.
 966  *   @result false if the iterator has been invalidated by changes to the registry, true otherwise. */
 967
 968         virtual bool isValid( void ) APPLE_KEXT_OVERRIDE;
 969
 970 /*! @function iterateAll
 971  *   @abstract Iterates all entries (with getNextObject) and returns a set of all returned entries.
 972  *   @discussion This method will reset, then iterate all entries in the iteration (with getNextObject).
 973  *   @result A set of entries returned by the iteration. The caller should release the set when it has finished with it. Zero is returned on a resource failure. */
 974
 975         virtual OSOrderedSet * iterateAll( void );
 976 };
 977
 978 #endif /* _IOKIT_IOREGISTRYENTRY_H */