[linux-2.6-block.git] / include / uapi / linux / const.h

/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
/* const.h: Macros for dealing with constants.  */

#ifndef _UAPI_LINUX_CONST_H
#define _UAPI_LINUX_CONST_H

/* Some constant macros are used in both assembler and
 * C code.  Therefore we cannot annotate them always with
 * 'UL' and other type specifiers unilaterally.  We
 * use the following macros to deal with this.
 *
 * Similarly, _AT() will cast an expression with a type in C, but
 * leave it unchanged in asm.
 */

#ifdef __ASSEMBLY__
#define _AC(X,Y)	X
#define _AT(T,X)	X
#else
#define __AC(X,Y)	(X##Y)
#define _AC(X,Y)	__AC(X,Y)
#define _AT(T,X)	((T)(X))
#endif

#define _UL(x)		(_AC(x, UL))
#define _ULL(x)		(_AC(x, ULL))

#define _BITUL(x)	(_UL(1) << (x))
#define _BITULL(x)	(_ULL(1) << (x))

#endif /* _UAPI_LINUX_CONST_H */
Commit	Line	Data
6f52b16c	1	/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
9d291e78 VG	2	/* const.h: Macros for dealing with constants. */
9d291e78 VG	3
2a6cc8a6 MY	4	#ifndef _UAPI_LINUX_CONST_H
2a6cc8a6 MY	5	#define _UAPI_LINUX_CONST_H
9d291e78 VG	6
	7	/* Some constant macros are used in both assembler and
	8	* C code. Therefore we cannot annotate them always with
6df95fd7	9	* 'UL' and other type specifiers unilaterally. We
9d291e78	10	* use the following macros to deal with this.
74ef649f JF	11	*
	12	* Similarly, _AT() will cast an expression with a type in C, but
	13	* leave it unchanged in asm.
9d291e78 VG	14	*/
	15
	16	#ifdef __ASSEMBLY__
	17	#define _AC(X,Y) X
74ef649f	18	#define _AT(T,X) X
9d291e78 VG	19	#else
	20	#define __AC(X,Y) (X##Y)
	21	#define _AC(X,Y) __AC(X,Y)
74ef649f	22	#define _AT(T,X) ((T)(X))
9d291e78 VG	23	#endif
9d291e78 VG	24
2dd8a62c MY	25	#define _UL(x) (_AC(x, UL))
	26	#define _ULL(x) (_AC(x, ULL))
	27
21e7bc60 MY	28	#define _BITUL(x) (_UL(1) << (x))
21e7bc60 MY	29	#define _BITULL(x) (_ULL(1) << (x))
2fc016c5	30
2a6cc8a6	31	#endif /* _UAPI_LINUX_CONST_H */