Emscripten

command

Module._free(arrayPointer);emcc C:\00_projects\wasm-experiment\main.c -o C:\00_projects\wasm-experiment\www\sort.html -s NO_EXIT_RUNTIME=1  -s "EXPORTED_RUNTIME_METHODS=['ccall','cwrap']" -s "EXPORTED_FUNCTIONS=['_malloc','_free']"

glue.js

const items = [-12, 4, 0, 2];
const arrayLength = items.length;
const bytesPerElement = Module.HEAP32.BYTES_PER_ELEMENT;

const arrayPointer = Module._malloc((arrayLength * bytesPerElement));

Module.HEAP32.set(items, (arrayPointer / bytesPerElement));

Module.ccall('selection_sort',
    null,
    ['number', 'number'],
    [arrayPointer, arrayLength]
);

main.c

#include <stdio.h>
#include <emscripten.h>
 
EMSCRIPTEN_KEEPALIVE void selection_sort (int *a, int n) {
    int i, j, m, t;

    for (i = 0; i < n; i++)
        printf("%d%s", a[i], i == n - 1 ? "\n" : " ");

    
    for (i = 0; i < n; i++) {
        for (j = i, m = i; j < n; j++) {
            if (a[j] < a[m]) {
                m = j;
            }
        }
        t = a[i];
        a[i] = a[m];
        a[m] = t;
    }
    
    for (i = 0; i < n; i++)
        printf("%d%s", a[i], i == n - 1 ? "\n" : " ");
}