Struct CMBlockBufferCustomBlockSource 

#[repr(C, packed(4))]
pub struct CMBlockBufferCustomBlockSource {
    pub version: u32,
    pub AllocateBlock: Option<unsafe extern "C-unwind" fn(*mut c_void, usize) -> *mut c_void>,
    pub FreeBlock: Option<unsafe extern "C-unwind" fn(*mut c_void, NonNull<c_void>, usize)>,
    pub refCon: *mut c_void,
}

Available on crate feature CMBlockBuffer only.

Used with functions that accept a memory block allocator, this structure allows a client to provide a custom facility for obtaining the memory block to be used in a CMBlockBuffer. The AllocateBlock function must be non-zero if the CMBlockBuffer code will need to call for allocation (not required if a previously-obtained memory block is provided to the CMBlockBuffer API). The FreeBlock() routine, if non-NULL, will be called once when the CMBlockBuffer is disposed. It will not be called if no memory block is ever allocated or supplied. The refCon will be passed to both the AllocateBlock and FreeBlock() calls. The client is responsible for its disposal (if any) during the FreeBlock() callback.

Note that for 64-bit architectures, this struct contains misaligned function pointers. To avoid link-time issues, it is recommended that clients fill CMBlockBufferCustomBlockSource’s function pointer fields by using assignment statements, rather than declaring them as global or static structs. The functions that accept CMBlockBufferCustomBlockSource pointers copy the fields and do not require the struct to stay valid after they return.

See also Apple’s documentation

Fields

version: u32

AllocateBlock: Option<unsafe extern "C-unwind" fn(*mut c_void, usize) -> *mut c_void>

FreeBlock: Option<unsafe extern "C-unwind" fn(*mut c_void, NonNull<c_void>, usize)>

refCon: *mut c_void

Trait Implementations

impl Clone for CMBlockBufferCustomBlockSource

fn clone(&self) -> CMBlockBufferCustomBlockSource

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for CMBlockBufferCustomBlockSource

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Encode for CMBlockBufferCustomBlockSource

Available on crate feature objc2 only.

const ENCODING: Encoding

The Objective-C type-encoding for this type.

impl PartialEq for CMBlockBufferCustomBlockSource

fn eq(&self, other: &CMBlockBufferCustomBlockSource) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl RefEncode for CMBlockBufferCustomBlockSource

Available on crate feature objc2 only.

const ENCODING_REF: Encoding

The Objective-C type-encoding for a reference of this type.

impl Copy for CMBlockBufferCustomBlockSource

impl StructuralPartialEq for CMBlockBufferCustomBlockSource