summaryrefslogtreecommitdiffstats
path: root/MdePkg/Library/BaseLib/Unaligned.c
blob: fef8343e94ff7faab24daccbc033812dd8556e0c (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
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
/** @file
  Unaligned access functions of BaseLib.

  Copyright (c) 2006, Intel Corporation
  All rights reserved. This program and the accompanying materials
  are licensed and made available under the terms and conditions of the BSD License
  which accompanies this distribution.  The full text of the license may be found at
  http://opensource.org/licenses/bsd-license.php

  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

  Module Name:  Unaligned.c

**/

//
// Include common header file for this module.
//
#include "CommonHeader.h"

/**
  Reads a 16-bit value from memory that may be unaligned.

  This function returns the 16-bit value pointed to by Buffer. The function
  guarantees that the read operation does not produce an alignment fault.

  If the Buffer is NULL, then ASSERT().

  @param  Buffer  Pointer to a 16-bit value that may be unaligned.

  @return *Uint16

**/
UINT16
EFIAPI
ReadUnaligned16 (
  IN      CONST UINT16              *Buffer
  )
{
  ASSERT (Buffer != NULL);

  return *Buffer;
}

/**
  Writes a 16-bit value to memory that may be unaligned.

  This function writes the 16-bit value specified by Value to Buffer. Value is
  returned. The function guarantees that the write operation does not produce
  an alignment fault.

  If the Buffer is NULL, then ASSERT().

  @param  Buffer  Pointer to a 16-bit value that may be unaligned.
  @param  Value   16-bit value to write to Buffer.

  @return Value

**/
UINT16
EFIAPI
WriteUnaligned16 (
  OUT     UINT16                    *Buffer,
  IN      UINT16                    Value
  )
{
  ASSERT (Buffer != NULL);

  return *Buffer = Value;
}

/**
  Reads a 24-bit value from memory that may be unaligned.

  This function returns the 24-bit value pointed to by Buffer. The function
  guarantees that the read operation does not produce an alignment fault.

  If the Buffer is NULL, then ASSERT().

  @param  Buffer  Pointer to a 24-bit value that may be unaligned.

  @return The value read.

**/
UINT32
EFIAPI
ReadUnaligned24 (
  IN      CONST UINT32              *Buffer
  )
{
  ASSERT (Buffer != NULL);

  return *Buffer & 0xffffff;
}

/**
  Writes a 24-bit value to memory that may be unaligned.

  This function writes the 24-bit value specified by Value to Buffer. Value is
  returned. The function guarantees that the write operation does not produce
  an alignment fault.

  If the Buffer is NULL, then ASSERT().

  @param  Buffer  Pointer to a 24-bit value that may be unaligned.
  @param  Value   24-bit value to write to Buffer.

  @return The value written.

**/
UINT32
EFIAPI
WriteUnaligned24 (
  OUT     UINT32                    *Buffer,
  IN      UINT32                    Value
  )
{
  ASSERT (Buffer != NULL);

  *Buffer = BitFieldWrite32 (*Buffer, 0, 23, Value);
  return Value;
}

/**
  Reads a 32-bit value from memory that may be unaligned.

  This function returns the 32-bit value pointed to by Buffer. The function
  guarantees that the read operation does not produce an alignment fault.

  If the Buffer is NULL, then ASSERT().

  @param  Buffer  Pointer to a 32-bit value that may be unaligned.

  @return *Uint32

**/
UINT32
EFIAPI
ReadUnaligned32 (
  IN      CONST UINT32              *Buffer
  )
{
  ASSERT (Buffer != NULL);

  return *Buffer;
}

/**
  Writes a 32-bit value to memory that may be unaligned.

  This function writes the 32-bit value specified by Value to Buffer. Value is
  returned. The function guarantees that the write operation does not produce
  an alignment fault.

  If the Buffer is NULL, then ASSERT().

  @param  Buffer  Pointer to a 32-bit value that may be unaligned.
  @param  Value   32-bit value to write to Buffer.

  @return Value

**/
UINT32
EFIAPI
WriteUnaligned32 (
  OUT     UINT32                    *Buffer,
  IN      UINT32                    Value
  )
{
  ASSERT (Buffer != NULL);

  return *Buffer = Value;
}

/**
  Reads a 64-bit value from memory that may be unaligned.

  This function returns the 64-bit value pointed to by Buffer. The function
  guarantees that the read operation does not produce an alignment fault.

  If the Buffer is NULL, then ASSERT().

  @param  Buffer  Pointer to a 64-bit value that may be unaligned.

  @return *Uint64

**/
UINT64
EFIAPI
ReadUnaligned64 (
  IN      CONST UINT64              *Buffer
  )
{
  ASSERT (Buffer != NULL);

  return *Buffer;
}

/**
  Writes a 64-bit value to memory that may be unaligned.

  This function writes the 64-bit value specified by Value to Buffer. Value is
  returned. The function guarantees that the write operation does not produce
  an alignment fault.

  If the Buffer is NULL, then ASSERT().

  @param  Buffer  Pointer to a 64-bit value that may be unaligned.
  @param  Value   64-bit value to write to Buffer.

  @return Value

**/
UINT64
EFIAPI
WriteUnaligned64 (
  OUT     UINT64                    *Buffer,
  IN      UINT64                    Value
  )
{
  ASSERT (Buffer != NULL);

  return *Buffer = Value;
}