/* Bump allocator on the initial memory pool.
 *
 * Temporary — until the PM-actor malloc path is implemented.
 * Thread-safe: no — __libc.heap_used is guarded by nothing yet.
 */

#include <stddef.h>
#include "libc.h"

void *malloc(size_t size)
{
    if (size == 0) size = 1;

    unsigned long heap = __libc.heap_base;
    unsigned long used = __libc.heap_used;

    if (used + size > __libc.heap_size)
        return 0;

    void *ptr = (void *)(heap + used);
    __libc.heap_used = used + size;
    return ptr;
}

void free(void *ptr)
{
    (void)ptr;
}

void *calloc(size_t nmemb, size_t size)
{
    size_t total = nmemb * size;
    void *p = malloc(total);
    if (!p) return 0;
    for (size_t i = 0; i < total; i++)
        ((unsigned char *)p)[i] = 0;
    return p;
}

void *realloc(void *ptr, size_t size)
{
    if (!ptr) return malloc(size);
    if (size == 0) { free(ptr); return 0; }
    /* Bump allocator cannot shrink/grow in place — always allocate + copy */
    void *newp = malloc(size);
    if (!newp) return 0;
    unsigned long old = __libc.heap_used - size;
    if (old > __libc.heap_used) old = __libc.heap_used;
    for (size_t i = 0; i < old; i++)
        ((unsigned char *)newp)[i] = ((unsigned char *)ptr)[i];
    return newp;
}