protected:
virtual void handleClose(IOService * client, IOOptionBits options);
The handleClose method closes the client's access to this object. * This implementation replaces the IOService definition of handleClose().
Name Description client Client requesting the close. options Options for the close. Set to zero.
protected:
virtual bool handleIsOpen(const IOService * client) const;
The handleIsOpen method determines whether the specified client, or any client if none is specificed, presently has an open on this object. * This implementation replaces the IOService definition of handleIsOpen().
Result: Returns true if the client was (or clients were) open, false otherwise.
Name Description client Client to check the open state of. Set to zero to check the open state of all clients.
protected:
virtual bool handleOpen(IOService * client, IOOptionBits options, void * access);
The handleOpen method grants or denies permission to access this object to an interested client. The argument is an IOStorageAccess value that specifies the level of access desired -- reader or reader-writer. * This method can be invoked to upgrade or downgrade the access level for an existing client as well. The previous access level will prevail for upgrades that fail, of course. A downgrade should never fail. If the new access level should be the same as the old for a given client, this method will do nothing and return success. In all cases, one, singular close-per-client is expected for all opens-per-client received. * This implementation replaces the IOService definition of handleOpen().
Result: Returns true if the open was successful, false otherwise.
Name Description client Client requesting the open. options Options for the open. Set to zero. access Access level for the open. Set to kAccessReader or kAccessReaderWriter.
public:
virtual void read(IOService * client, UInt64 byteStart, IOMemoryDescriptor * buffer, IOStorageCompletion completion);
Read data from the storage object at the specified byte offset into the specified buffer, asynchronously. When the read completes, the caller will be notified via the specified completion action. * The buffer will be retained for the duration of the read. * For simple partition schemes, the default behavior is to simply pass the read through to the provider media. More complex partition schemes such as RAID will need to do extra processing here.
Name Description client Client requesting the read. byteStart Starting byte offset for the data transfer. buffer Buffer for the data transfer. The size of the buffer implies the size of the data transfer. completion Completion routine to call once the data transfer is complete.
public:
virtual void write(IOService * client, UInt64 byteStart, IOMemoryDescriptor * buffer, IOStorageCompletion completion);
Write data into the storage object at the specified byte offset from the specified buffer, asynchronously. When the write completes, the caller will be notified via the specified completion action. * The buffer will be retained for the duration of the write. * For simple partition schemes, the default behavior is to simply pass the write through to the provider media. More complex partition schemes such as RAID will need to do extra processing here.
Name Description client Client requesting the write. byteStart Starting byte offset for the data transfer. buffer Buffer for the data transfer. The size of the buffer implies the size of the data transfer. completion Completion routine to call once the data transfer is complete.
© 2000 Apple Computer, Inc. (Last Updated 2/23/2000)