Parameters 🔗

user_data	in	User pointer passed to unimemfunc.
allocf	in	Memory management routine.

Return Value 🔗

UNI_OK	If the memory allocator was modified.
UNI_FEATURE_DISABLED	If allocf is null and Unicorn was built without support for the C standard library memory allocator.

Discussion 🔗

Sets allocf as the implementation for dynamic memory allocations. If allocf is null then the implementation reverts to its default allocator which may be the C standard allocator or a dummy allocator that always fails to allocate memory. The latter is only present when the C standard library allocators are disabled.

Support for C standard library allocators must be enabled in the JSON configuration file. If the standard allocators are not enabled, then dummy allocators that always return NULL are used. In this case, a custom allocator must be supplied.

{
    "hasStandardAllocators": true
}

Examples 🔗

This example registers a custom memory allocator with Unicorn. In the example, the custom allocator wraps the C standard memory allocators, however, this is redundant because Unicorn already initializes with a custom allocator that wraps the C standard allocators. They are wrapped here for example purposes only. An actual implementation would implement and wrap its own custom memory allocator.

#include <unicorn.h>
#include <stdlib.h>

static void *allocfree(void *ud, void *ptr, size_t osize, size_t nsize)
{
    if (nsize == 0)
    {
        free(ptr);
        return NULL;
    }
    else
    {
        return realloc(ptr, nsize);
    }
}

int main(void)
{
    uni_setmemfunc(NULL, allocfree);
    return 0;
}