blob: 992e4b18bead034afcd25a7a9b617c8f17bc1548 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
|
/* CC0 (Public domain) - see LICENSE file for details */
#ifndef CCAN_PTRINT_H
#define CCAN_PTRINT_H
#include "config.h"
#include <stddef.h>
#include <ccan/build_assert/build_assert.h>
/*
* This is a deliberately incomplete type, because it should never be
* dereferenced - instead it marks pointer values which are actually
* encoding integers
*/
typedef struct ptrint ptrint_t;
static inline ptrdiff_t ptr2int(const ptrint_t *p)
{
/*
* ptrdiff_t is the right size by definition, but to avoid
* surprises we want a warning if the user can't fit at least
* a regular int in there
*/
BUILD_ASSERT(sizeof(int) <= sizeof(ptrdiff_t));
return (const char *)p - (const char *)NULL;
}
static inline ptrint_t *int2ptr(ptrdiff_t i)
{
return (ptrint_t *)((char *)NULL + i);
}
#endif /* CCAN_PTRINT_H */
|
