Function cbm_arena_alloc

internal/cbm/arena.c:35–55

}

void *cbm_arena_alloc(CBMArena *a, size_t n) {
    if (!a || n == 0) {
        return NULL;
    }
    // 8-byte alignment
    n = (n + 7) & ~(size_t)7;

    if (a->nblocks == 0) {
        return NULL;
    }

    if (a->used + n > a->block_size) {
        if (!arena_grow(a, n)) {
            return NULL;
        }
    }

    char *ptr = a->blocks[a->nblocks - SKIP_ONE] + a->used;
    a->used += n;
    return ptr;
}

char *cbm_arena_strdup(CBMArena *a, const char *s) {
    if (!s)