use libc::{
    c_void,
    size_t,
    memcpy,
};

use crate::webassembly::{Instance};

/// emscripten: _emscripten_memcpy_big
pub extern "C" fn _emscripten_memcpy_big(dest: u32, src: u32, len: u32, instance: &mut Instance) -> u32 {
    let dest_addr = instance.memory_offset_addr(0, dest as usize) as *mut c_void;
    let src_addr = instance.memory_offset_addr(0, src as usize) as *mut c_void;
    unsafe { memcpy(dest_addr, src_addr, len as size_t); }
    dest
}

/// emscripten: getTotalMemory
pub extern "C" fn get_total_memory(instance: &mut Instance) -> u32 {
    instance.memories[0].current_size()
}

/// emscripten: enlargeMemory
pub extern "C" fn enlarge_memory() {
    // stub
}