Interface VkAllocationFunctionI

All Superinterfaces:
CallbackI, Pointer
All Known Implementing Classes:
VkAllocationFunction
Functional Interface:
This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface public interface VkAllocationFunctionI extends CallbackI
Application-defined memory allocation function.
C Specification

The type of pfnAllocation is:


 typedef void* (VKAPI_PTR *PFN_vkAllocationFunction)(
     void*                                       pUserData,
     size_t                                      size,
     size_t                                      alignment,
     VkSystemAllocationScope                     allocationScope);
Description

If pfnAllocation is unable to allocate the requested memory, it must return NULL. If the allocation was successful, it must return a valid pointer to memory allocation containing at least size bytes, and with the pointer value being a multiple of alignment.

Note

Correct Vulkan operation cannot be assumed if the application does not follow these rules.

For example, pfnAllocation (or pfnReallocation) could cause termination of running Vulkan instance(s) on a failed allocation for debugging purposes, either directly or indirectly. In these circumstances, it cannot be assumed that any part of any affected VkInstance objects are going to operate correctly (even DestroyInstance), and the application must ensure it cleans up properly via other means (e.g. process termination).

If pfnAllocation returns NULL, and if the implementation is unable to continue correct processing of the current command without the requested allocation, it must treat this as a runtime error, and generate ERROR_OUT_OF_HOST_MEMORY at the appropriate time for the command in which the condition was detected, as described in Return Codes.

If the implementation is able to continue correct processing of the current command without the requested allocation, then it may do so, and must not generate ERROR_OUT_OF_HOST_MEMORY as a result of this failed allocation.

See Also

VkAllocationCallbacks

  • Nested Class Summary

    Nested classes/interfaces inherited from interface org.lwjgl.system.Pointer

    Pointer.Default
  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final FFICIF
     

    Fields inherited from interface org.lwjgl.system.Pointer

    BITS32, BITS64, CLONG_SHIFT, CLONG_SIZE, POINTER_SHIFT, POINTER_SIZE
  • Method Summary

    Modifier and Type
    Method
    Description
    default void
    callback(long ret, long args)
    The Java method that will be called from native code when the native callback function is invoked.
    default FFICIF
    Returns the libffi Call Interface for this callback function.
    long
    invoke(long pUserData, long size, long alignment, int allocationScope)
    Application-defined memory allocation function.

    Methods inherited from interface org.lwjgl.system.CallbackI

    address
  • Field Details

    • CIF

      static final FFICIF CIF
  • Method Details

    • getCallInterface

      default FFICIF getCallInterface()
      Description copied from interface: CallbackI
      Returns the libffi Call Interface for this callback function. [INTERNAL API]
      Specified by:
      getCallInterface in interface CallbackI
      Returns:
      the CIF structure for this callback function
    • callback

      default void callback(long ret, long args)
      Description copied from interface: CallbackI
      The Java method that will be called from native code when the native callback function is invoked.
      Specified by:
      callback in interface CallbackI
      Parameters:
      ret - a pointer to the memory used for the function's return value.

      If the function is declared as returning void, then this value is garbage and should not be used.

      Otherwise, the callback must fill the object to which this points, following the same special promotion behavior as LibFFI.ffi_call(org.lwjgl.system.libffi.FFICIF, long, java.nio.ByteBuffer, org.lwjgl.PointerBuffer). That is, in most cases, ret points to an object of exactly the size of the type specified when CIF was constructed. However, integral types narrower than the system register size are widened. In these cases your program may assume that ret points to an ffi_arg object.

      args - a vector of pointers to memory holding the arguments to the function
    • invoke

      long invoke(long pUserData, long size, long alignment, int allocationScope)
      Application-defined memory allocation function.
      Parameters:
      pUserData - the value specified for VkAllocationCallbacks::pUserData in the allocator specified by the application.
      size - the size in bytes of the requested allocation.
      alignment - the requested alignment of the allocation in bytes and must be a power of two.
      allocationScope - a VkSystemAllocationScope value specifying the allocation scope of the lifetime of the allocation, as described here.