1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Declare directives for structure packing. No padding will be provided
4 * between the members of packed structures, and therefore, there is no
5 * guarantee that structure members will be aligned.
6 *
7 * Declaring packed structures is compiler specific. In order to handle all
8 * cases, packed structures should be delared as:
9 *
10 * #include <packed_section_start.h>
11 *
12 * typedef BWL_PRE_PACKED_STRUCT struct foobar_t {
13 * some_struct_members;
14 * } BWL_POST_PACKED_STRUCT foobar_t;
15 *
16 * #include <packed_section_end.h>
17 *
18 *
19 * Copyright (C) 1999-2019, Broadcom.
20 *
21 * Unless you and Broadcom execute a separate written software license
22 * agreement governing use of this software, this software is licensed to you
23 * under the terms of the GNU General Public License version 2 (the "GPL"),
24 * available at http://www.broadcom.com/licenses/GPLv2.php, with the
25 * following added to such license:
26 *
27 * As a special exception, the copyright holders of this software give you
28 * permission to link this software with independent modules, and to copy and
29 * distribute the resulting executable under terms of your choice, provided that
30 * you also meet, for each linked independent module, the terms and conditions of
31 * the license of that module. An independent module is a module which is not
32 * derived from this software. The special exception does not apply to any
33 * modifications of the software.
34 *
35 * Notwithstanding the above, under no circumstances may you combine this
36 * software in any way with any other Broadcom software provided under a license
37 * other than the GPL, without Broadcom's express prior written consent.
38 *
39 *
40 * <<Broadcom-WL-IPTag/Open:>>
41 *
42 * $Id: packed_section_start.h 776894 2018-08-16 05:50:57Z $
43 */
44
45 #ifndef _alignment_test_
46 #define _alignment_test_
47
48 /* ASSERT default packing */
49 typedef struct T4 {
50 uint8 a;
51 uint32 b;
52 uint16 c;
53 uint8 d;
54 } T4_t;
55
56 /* 4 byte alignment support */
57 /*
58 * a . . .
59 * b b b b
60 * c c d .
61 */
62
63 /*
64 * Below function is meant to verify that this file is compiled with the default alignment of 4.
65 * Function will fail to compile if the condition is not met.
66 */
67 #ifdef __GNUC__
68 #define VARIABLE_IS_NOT_USED __attribute__ ((unused))
69 #else
70 #define VARIABLE_IS_NOT_USED
71 #endif // endif
72 static void alignment_test(void);
73 static void
alignment_test(void)74 VARIABLE_IS_NOT_USED alignment_test(void)
75 {
76 /* verify 4 byte alignment support */
77 STATIC_ASSERT(sizeof(T4_t) == 12);
78 }
79 #endif /* _alignment_test_ */
80
81 /* Error check - BWL_PACKED_SECTION is defined in packed_section_start.h
82 * and undefined in packed_section_end.h. If it is already defined at this
83 * point, then there is a missing include of packed_section_end.h.
84 */
85 #ifdef BWL_PACKED_SECTION
86 #error "BWL_PACKED_SECTION is already defined!"
87 #else
88 #define BWL_PACKED_SECTION
89 #endif // endif
90
91 #if defined(BWL_DEFAULT_PACKING)
92 /* generate an error if BWL_DEFAULT_PACKING is defined */
93 #error "BWL_DEFAULT_PACKING not supported any more."
94 #endif /* BWL_PACKED_SECTION */
95
96 /* Declare compiler-specific directives for structure packing. */
97 #if defined(__GNUC__) || defined(__lint)
98 #define BWL_PRE_PACKED_STRUCT
99 #define BWL_POST_PACKED_STRUCT __attribute__ ((packed))
100 #elif defined(__CC_ARM)
101 #define BWL_PRE_PACKED_STRUCT __packed
102 #define BWL_POST_PACKED_STRUCT
103 #else
104 #error "Unknown compiler!"
105 #endif // endif
106