xref: /onnv-gate/usr/src/lib/libntfs/common/include/ntfs/support.h (revision 9663:ace9a2ac3683)
1 /*
2  * support.h - Various useful things. Part of the Linux-NTFS project.
3  *
4  * Copyright (c) 2000-2004 Anton Altaparmakov
5  * Copyright (c)      2006 Szabolcs Szakacsits
6  * Copyright (c)      2006 Yura Pakhuchiy
7  *
8  * This program/include file is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as published
10  * by the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program/include file is distributed in the hope that it will be
14  * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
15  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program (in the main directory of the Linux-NTFS
20  * distribution in the file COPYING); if not, write to the Free Software
21  * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
22  */
23 
24 #ifndef _NTFS_SUPPORT_H
25 #define _NTFS_SUPPORT_H
26 
27 #ifdef HAVE_CONFIG_H
28 #include "config.h"
29 #endif
30 
31 #ifdef HAVE_STDDEF_H
32 #include <stddef.h>
33 #endif
34 
35 #ifdef HAVE_STDLIB_H
36 #include <stdlib.h>
37 #endif
38 
39 #include "logging.h"
40 
41 /*
42  * Our mailing list. Use this define to prevent typos in email address.
43  */
44 #define NTFS_DEV_LIST	"linux-ntfs-dev@lists.sf.net"
45 
46 /*
47  * Generic macro to convert pointers to values for comparison purposes.
48  */
49 #ifndef p2n
50 #define p2n(p)		((ptrdiff_t)((ptrdiff_t*)(p)))
51 #endif
52 
53 /*
54  * The classic min and max macros.
55  */
56 #ifndef min
57 #define min(a,b)	((a) <= (b) ? (a) : (b))
58 #endif
59 
60 #ifndef max
61 #define max(a,b)	((a) >= (b) ? (a) : (b))
62 #endif
63 
64 /*
65  * Useful macro for determining the offset of a struct member.
66  */
67 #ifndef offsetof
68 #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
69 #endif
70 
71 /*
72  * Round up and down @num to 2 in power of @order.
73  */
74 #define ROUND_UP(num,order)	(((num) + ((1 << (order)) - 1)) & \
75 				~((1 << (order)) - 1))
76 #define ROUND_DOWN(num,order)	((num) & ~((1 << (order)) - 1))
77 
78 /*
79  * Simple bit operation macros. NOTE: These are NOT atomic.
80  */
81 #define test_bit(bit, var)	      ((var) & (1 << (bit)))
82 #define set_bit(bit, var)	      (var) |= 1 << (bit)
83 #define clear_bit(bit, var)	      (var) &= ~(1 << (bit))
84 
85 #ifdef __sun
86 #define test_and_set_bit(bit, var)	_test_and_set_bit(bit, &var)
_test_and_set_bit(unsigned long bit,unsigned long * var)87 static __inline__ BOOL _test_and_set_bit(unsigned long bit, unsigned long *var)
88 {
89 	const BOOL old_state = test_bit(bit, *var);
90 	set_bit(bit, *var);
91 	return old_state;
92 }
93 
94 #define test_and_clear_bit(bit, var)	_test_and_clear_bit(bit, &var)
_test_and_clear_bit(unsigned long bit,unsigned long * var)95 static __inline__ BOOL _test_and_clear_bit(unsigned long bit, unsigned long *var)
96 {
97 	const BOOL old_state = test_bit(bit, *var);
98 	clear_bit(bit, *var);
99 	return old_state;
100 }
101 #else /* !__sun */
102 #define test_and_set_bit(bit, var)			\
103 ({							\
104 	const BOOL old_state = test_bit(bit, var);	\
105 	set_bit(bit, var);				\
106 	old_state;					\
107 })
108 
109 #define test_and_clear_bit(bit, var)			\
110 ({							\
111 	const BOOL old_state = test_bit(bit, var);	\
112 	clear_bit(bit, var);				\
113 	old_state;					\
114 })
115 #endif /* __sun */
116 
117 /* Memory allocation with logging. */
118 extern void *ntfs_calloc(size_t size);
119 extern void *ntfs_malloc(size_t size);
120 
121 #endif /* defined _NTFS_SUPPORT_H */
122