Struct libffi::low::CodePtr
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[src]
#[repr(C)]pub struct CodePtr(pub *mut c_void);
Wraps a function pointer of unknown type.
This is used to make the API a bit easier to understand, and as a
simple type lint. As a repr(C) struct of one element, it should
be safe to transmute between CodePtr and *mut c_void, or between
collections thereof.
Methods
impl CodePtr[src]
fn from_fun(fun: unsafe extern fn()) -> Self
Initializes a code pointer from a function pointer.
This is useful mainly for talking to C APIs that take untyped
callbacks specified in the API as having type void(*)().
fn from_ptr(fun: *const c_void) -> Self
Initializes a code pointer from a void pointer.
This is the other common type used in APIs (or at least in libffi) for untyped callback arguments.
fn as_fun(&self) -> &unsafe extern fn()
Gets the code pointer typed as a C function pointer.
This is useful mainly for talking to C APIs that take untyped
callbacks specified in the API as having type void(*)().
Safety
There is no checking that the returned type reflects the actual
parameter and return types of the function. Unless the C
function actually has type void(*)(), it will need to be
cast before it is called.
unsafe fn as_safe_fun(&self) -> &extern fn()
Gets the code pointer typed as a “safe” C function pointer.
This is useful mainly for talking to C APIs that take untyped
callbacks specified in the API as having type void(*)().
Safety
There isn’t necessarily anything actually safe about the resulting
function pointer—it’s up to the caller to know what they’re
doing within the unsafety boundary, or undefined behavior may
result. In particular,
there is no checking that the returned type reflects the actual
parameter and return types of the function. Unless the C
function actually has type void(*)(), it will need to be
cast before it is called.
fn as_ptr(&self) -> *const c_void
Gets the code pointer typed as a const void*.
This is the other common type used in APIs (or at least in libffi) for untyped callback arguments.
fn as_mut_ptr(&self) -> *mut c_void
Gets the code pointer typed as a void*.
This is the other common type used in APIs (or at least in libffi) for untyped callback arguments.
Trait Implementations
impl Clone for CodePtr[src]
fn clone(&self) -> CodePtr
Returns a copy of the value. Read more
fn clone_from(&mut self, source: &Self)1.0.0
Performs copy-assignment from source. Read more
impl Copy for CodePtr[src]
impl Debug for CodePtr[src]
impl Hash for CodePtr[src]
fn hash<__H: Hasher>(&self, __arg_0: &mut __H)
Feeds this value into the state given, updating the hasher as necessary.
fn hash_slice<H>(data: &[Self], state: &mut H) where H: Hasher1.3.0
Feeds a slice of this type into the state provided.