| Index: fusl/src/malloc/memalign.c
|
| diff --git a/fusl/src/malloc/memalign.c b/fusl/src/malloc/memalign.c
|
| new file mode 100644
|
| index 0000000000000000000000000000000000000000..006bd21c7673858a0206d8d131b9971a1d8bcad4
|
| --- /dev/null
|
| +++ b/fusl/src/malloc/memalign.c
|
| @@ -0,0 +1,57 @@
|
| +#include <stdlib.h>
|
| +#include <stdint.h>
|
| +#include <errno.h>
|
| +#include "libc.h"
|
| +
|
| +/* This function should work with most dlmalloc-like chunk bookkeeping
|
| + * systems, but it's only guaranteed to work with the native implementation
|
| + * used in this library. */
|
| +
|
| +void *__memalign(size_t align, size_t len)
|
| +{
|
| + unsigned char *mem, *new, *end;
|
| + size_t header, footer;
|
| +
|
| + if ((align & -align) != align) {
|
| + errno = EINVAL;
|
| + return NULL;
|
| + }
|
| +
|
| + if (len > SIZE_MAX - align) {
|
| + errno = ENOMEM;
|
| + return NULL;
|
| + }
|
| +
|
| + if (align <= 4*sizeof(size_t)) {
|
| + if (!(mem = malloc(len)))
|
| + return NULL;
|
| + return mem;
|
| + }
|
| +
|
| + if (!(mem = malloc(len + align-1)))
|
| + return NULL;
|
| +
|
| + new = (void *)((uintptr_t)mem + align-1 & -align);
|
| + if (new == mem) return mem;
|
| +
|
| + header = ((size_t *)mem)[-1];
|
| +
|
| + if (!(header & 7)) {
|
| + ((size_t *)new)[-2] = ((size_t *)mem)[-2] + (new-mem);
|
| + ((size_t *)new)[-1] = ((size_t *)mem)[-1] - (new-mem);
|
| + return new;
|
| + }
|
| +
|
| + end = mem + (header & -8);
|
| + footer = ((size_t *)end)[-2];
|
| +
|
| + ((size_t *)mem)[-1] = header&7 | new-mem;
|
| + ((size_t *)new)[-2] = footer&7 | new-mem;
|
| + ((size_t *)new)[-1] = header&7 | end-new;
|
| + ((size_t *)end)[-2] = footer&7 | end-new;
|
| +
|
| + free(mem);
|
| + return new;
|
| +}
|
| +
|
| +weak_alias(__memalign, memalign);
|
|
|