1 /*
2 * Declare directives for structure packing. No padding will be provided
3 * between the members of packed structures, and therefore, there is no
4 * guarantee that structure members will be aligned.
5 *
6 * Declaring packed structures is compiler specific. In order to handle all
7 * cases, packed structures should be delared as:
8 *
9 * #include <packed_section_start.h>
10 *
11 * typedef BWL_PRE_PACKED_STRUCT struct foobar_t {
12 * some_struct_members;
13 * } BWL_POST_PACKED_STRUCT foobar_t;
14 *
15 * #include <packed_section_end.h>
16 *
17 *
18 * Copyright (C) 2020, Broadcom.
19 *
20 * Unless you and Broadcom execute a separate written software license
21 * agreement governing use of this software, this software is licensed to you
22 * under the terms of the GNU General Public License version 2 (the "GPL"),
23 * available at http://www.broadcom.com/licenses/GPLv2.php, with the
24 * following added to such license:
25 *
26 * As a special exception, the copyright holders of this software give you
27 * permission to link this software with independent modules, and to copy and
28 * distribute the resulting executable under terms of your choice, provided that
29 * you also meet, for each linked independent module, the terms and conditions of
30 * the license of that module. An independent module is a module which is not
31 * derived from this software. The special exception does not apply to any
32 * modifications of the software.
33 *
34 *
35 * <<Broadcom-WL-IPTag/Dual:>>
36 */
37
38 /* EFI does not support STATIC_ASSERT */
39 #if defined(EFI)
40 #define _alignment_test_
41 #endif /* EFI */
42
43 #ifndef _alignment_test_
44 #define _alignment_test_
45
46 /* ASSERT default packing */
47 typedef struct T4 {
48 uint8 a;
49 uint32 b;
50 uint16 c;
51 uint8 d;
52 } T4_t;
53
54 /* 4 byte alignment support */
55 /*
56 * a . . .
57 * b b b b
58 * c c d .
59 */
60
61 /*
62 * Below function is meant to verify that this file is compiled with the default alignment of 4.
63 * Function will fail to compile if the condition is not met.
64 */
65 #ifdef __GNUC__
66 #define VARIABLE_IS_NOT_USED __attribute__ ((unused))
67 #else
68 #define VARIABLE_IS_NOT_USED
69 #endif
70 static void alignment_test(void);
71 static void
alignment_test(void)72 VARIABLE_IS_NOT_USED alignment_test(void)
73 {
74 /* verify 4 byte alignment support */
75 STATIC_ASSERT(sizeof(T4_t) == 12);
76 }
77 #endif /* _alignment_test_ */
78
79 /* Error check - BWL_PACKED_SECTION is defined in packed_section_start.h
80 * and undefined in packed_section_end.h. If it is already defined at this
81 * point, then there is a missing include of packed_section_end.h.
82 */
83 #ifdef BWL_PACKED_SECTION
84 #error "BWL_PACKED_SECTION is already defined!"
85 #else
86 #define BWL_PACKED_SECTION
87 #endif
88
89 #if defined(BWL_DEFAULT_PACKING)
90 /* generate an error if BWL_DEFAULT_PACKING is defined */
91 #error "BWL_DEFAULT_PACKING not supported any more."
92 #endif /* BWL_PACKED_SECTION */
93
94 #if defined(_MSC_VER)
95 #pragma warning(disable:4103)
96 #pragma pack(push)
97 #pragma pack(1)
98 #endif
99
100 #if defined(__GNUC__) && defined(EFI)
101 #pragma pack(push)
102 #pragma pack(1)
103 #endif
104
105 /* Declare compiler-specific directives for structure packing. */
106 #if defined(_MSC_VER)
107 #define BWL_PRE_PACKED_STRUCT
108 #define BWL_POST_PACKED_STRUCT
109 #elif defined(__GNUC__) || defined(__lint)
110 #define BWL_PRE_PACKED_STRUCT
111 #define BWL_POST_PACKED_STRUCT __attribute__ ((packed))
112 #elif defined(__CC_ARM)
113 #define BWL_PRE_PACKED_STRUCT __packed
114 #define BWL_POST_PACKED_STRUCT
115 #else
116 #error "Unknown compiler!"
117 #endif
118