void *
crt_memalign (size_t alignment, size_t size)
{
void *mem, *base;
unsigned long tot_addr, tot_end_addr, addr, end_addr;
struct heap_free_area **heap = &__malloc_heap;
/* Make SIZE something we like. */
size = HEAP_ADJUST_SIZE (size);
/* Use malloc to do the initial allocation, since it deals with getting
system memory. We over-allocate enough to be sure that we'll get
enough memory to hold a properly aligned block of size SIZE,
_somewhere_ in the result. */
mem = crt_malloc (size + 2 * alignment);
if (! mem)
/* Allocation failed, we can't do anything. */
return 0;
if (alignment < MALLOC_ALIGNMENT)
return mem;
/* Remember the base-address, of the allocation, although we normally
use the user-address for calculations, since that's where the
alignment matters. */
base = MALLOC_BASE (mem);
/* The bounds of the initial allocation. */
tot_addr = (unsigned long)mem;
tot_end_addr = (unsigned long)base + MALLOC_SIZE (mem);
/* Find a likely place inside MEM with the right alignment. */
addr = MALLOC_ROUND_UP (tot_addr, alignment);
/* Unless TOT_ADDR was already aligned correctly, we need to return the
initial part of MEM to the heap. */
if (addr != tot_addr)
{
size_t init_size = addr - tot_addr;
/* Ensure that memory returned to the heap is large enough. */
if (init_size < HEAP_MIN_SIZE)
{
addr = MALLOC_ROUND_UP (tot_addr + HEAP_MIN_SIZE, alignment);
init_size = addr - tot_addr;
}
__heap_free (heap, base, init_size);
/* Remember that we've freed the initial part of MEM. */
(char*)base += init_size;
}
/* Return the end part of MEM to the heap, unless it's too small. */
end_addr = addr + size;
if (end_addr + MALLOC_REALLOC_MIN_FREE_SIZE < tot_end_addr)
__heap_free (heap, (void *)end_addr, tot_end_addr - end_addr);
else
/* We didn't free the end, so include it in the size. */
end_addr = tot_end_addr;
return MALLOC_SETUP (base, end_addr - (unsigned long)base);
}
// Modify the local functions below should you wish to use some other memory routines
// for malloc(), free()
static void* XXH_malloc(size_t s) { return crt_malloc(s); }
