Struct IOUSBHostStream

Source

pub struct IOUSBHostStream { /* private fields */ }

Available on crate features IOUSBHostIOSource and IOUSBHostStream only.

Expand description

Apple’s documentation

Implementations§

Source §

impl IOUSBHostStream

Source

pub unsafe fn hostPipe(&self) -> Retained<IOUSBHostPipe>

Available on crate feature IOUSBHostPipe only.

Returns the IOUSBHostPipe this stream was created from

Returns: IOUSBHostPipe pointer

Source

pub unsafe fn streamID(&self) -> NSUInteger

Returns streamID associated with this IOUSBHostStream.

Returns: streamID

Source

pub unsafe fn abortWithOption_error( &self, option: IOUSBHostAbortOption, ) -> Result<(), Retained<NSError>>

Available on crate feature IOUSBHostDefinitions only.

Abort pending I/O requests.

A stream context must be set as non-active on the device via an out-of-band (class-defined) mechanism before this method is called (USB 3.1 8.12.1.4). A non-active stream will not be selected by the device to become the current stream on the endpoint.

Parameter option: IOUSBHostAbortOption by default IOUSBHostAbortOptionSynchronous is used

Returns: YES on success, an IOReturn error code will be reported on failure

Source

pub unsafe fn abortWithError(&self) -> Result<(), Retained<NSError>>

Abort pending I/O requests.

A stream context must be set as non-active on the device via an out-of-band (class-defined) mechanism before this method is called (USB 3.1 8.12.1.4). A non-active stream will not be selected by the device to become the current stream on the endpoint.

Returns: YES on success, an IOReturn error code will be reported on failure

Source

pub unsafe fn sendIORequestWithData_bytesTransferred_error( &self, data: Option<&NSMutableData>, bytes_transferred: *mut NSUInteger, ) -> Result<(), Retained<NSError>>

Send an IO request on the source

This method will send a synchronous request on the IO source, and will not return until the request is complete. CompletionTimeouts are not applicable to streams.

Parameter data: NSData* pointer containing the buffer to use for the transfer

Parameter bytesTransferred: NSUInteger reference which will be updated with the bytes transferred during the request

Returns: YES on success, an IOReturn error code will be reported on failure

§Safety

bytes_transferred must be a valid pointer or null.

Source

pub unsafe fn enqueueIORequestWithData_error_completionHandler( &self, data: Option<&NSMutableData>, error: Option<&mut Option<Retained<NSError>>>, completion_handler: IOUSBHostCompletionHandler, ) -> bool

Available on crate features IOUSBHostDefinitions and block2 only.

Enqueue an IO request on the source

This method is used to issue an asynchronous I/O request on the IO source. CompletionTimeouts are not applicable to streams.

Parameter data: pointer containing the buffer to use for the transfer

Returns: YES on success, an IOReturn error code will be reported on failure

§Safety

completion_handler must be a valid pointer or null.

Source §

impl IOUSBHostStream

Methods declared on superclass IOUSBHostIOSource.

Source

pub unsafe fn init(this: Allocated<Self>) -> Retained<Self>

Source §

impl IOUSBHostStream

Methods declared on superclass NSObject.

Source

pub unsafe fn new() -> Retained<Self>

Methods from Deref<Target = IOUSBHostIOSource>§

Source

pub unsafe fn hostInterface(&self) -> Retained<IOUSBHostInterface>

Available on crate features IOUSBHostInterface and IOUSBHostObject only.

Retrieve the source’s IOUSBHostInterface

Returns: IOUSBHostInterface pointer that the IOSource was created from.

Source

pub unsafe fn deviceAddress(&self) -> NSUInteger

Retrieve the device’s address

Returns: Current address of the device

Source

pub unsafe fn endpointAddress(&self) -> NSUInteger

Retrieve the IOSource’s endpoint address

Returns: Current address of the endpoint

Methods from Deref<Target = NSObject>§

Source

pub fn doesNotRecognizeSelector(&self, sel: Sel) -> !

Handle messages the object doesn’t recognize.

See Apple’s documentation for details.

Methods from Deref<Target = AnyObject>§

Source

pub fn class(&self) -> &'static AnyClass

Dynamically find the class of this object.

§Panics

May panic if the object is invalid (which may be the case for objects returned from unavailable init/new methods).

§Example

Check that an instance of NSObject has the precise class NSObject.

use objc2::ClassType;
use objc2::runtime::NSObject;

let obj = NSObject::new();
assert_eq!(obj.class(), NSObject::class());

Source

pub unsafe fn get_ivar<T>(&self, name: &str) -> &T
where T: Encode,

👎Deprecated: this is difficult to use correctly, use Ivar::load instead.

Use Ivar::load instead.

§Safety

The object must have an instance variable with the given name, and it must be of type T.

See Ivar::load_ptr for details surrounding this.

Source

pub fn downcast_ref<T>(&self) -> Option<&T>
where T: DowncastTarget,

Attempt to downcast the object to a class of type T.

This is the reference-variant. Use Retained::downcast if you want to convert a retained object to another type.

§Mutable classes

Some classes have immutable and mutable variants, such as NSString and NSMutableString.

When some Objective-C API signature says it gives you an immutable class, it generally expects you to not mutate that, even though it may technically be mutable “under the hood”.

So using this method to convert a NSString to a NSMutableString, while not unsound, is generally frowned upon unless you created the string yourself, or the API explicitly documents the string to be mutable.

See Apple’s documentation on mutability and on isKindOfClass: for more details.

§Generic classes

Objective-C generics are called “lightweight generics”, and that’s because they aren’t exposed in the runtime. This makes it impossible to safely downcast to generic collections, so this is disallowed by this method.

You can, however, safely downcast to generic collections where all the type-parameters are AnyObject.

§Panics

This works internally by calling isKindOfClass:. That means that the object must have the instance method of that name, and an exception will be thrown (if CoreFoundation is linked) or the process will abort if that is not the case. In the vast majority of cases, you don’t need to worry about this, since both root objects NSObject and NSProxy implement this method.

§Examples

Cast an NSString back and forth from NSObject.

use objc2::rc::Retained;
use objc2_foundation::{NSObject, NSString};

let obj: Retained<NSObject> = NSString::new().into_super();
let string = obj.downcast_ref::<NSString>().unwrap();
// Or with `downcast`, if we do not need the object afterwards
let string = obj.downcast::<NSString>().unwrap();

Try (and fail) to cast an NSObject to an NSString.

use objc2_foundation::{NSObject, NSString};

let obj = NSObject::new();
assert!(obj.downcast_ref::<NSString>().is_none());

Try to cast to an array of strings.

use objc2_foundation::{NSArray, NSObject, NSString};

let arr = NSArray::from_retained_slice(&[NSObject::new()]);
// This is invalid and doesn't type check.
let arr = arr.downcast_ref::<NSArray<NSString>>();

This fails to compile, since it would require enumerating over the array to ensure that each element is of the desired type, which is a performance pitfall.

Downcast when processing each element instead.

use objc2_foundation::{NSArray, NSObject, NSString};

let arr = NSArray::from_retained_slice(&[NSObject::new()]);

for elem in arr {
    if let Some(data) = elem.downcast_ref::<NSString>() {
        // handle `data`
    }
}