1 /******************************************************************************
2  *
3  * Module Name: uthex -- Hex/ASCII support functions
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2020, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43 
44 #include "acpi.h"
45 #include "accommon.h"
46 
47 #define _COMPONENT          ACPI_COMPILER
48         ACPI_MODULE_NAME    ("uthex")
49 
50 
51 /* Hex to ASCII conversion table */
52 
53 static const char           AcpiGbl_HexToAscii[] =
54 {
55     '0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'
56 };
57 
58 
59 /*******************************************************************************
60  *
61  * FUNCTION:    AcpiUtHexToAsciiChar
62  *
63  * PARAMETERS:  Integer             - Contains the hex digit
64  *              Position            - bit position of the digit within the
65  *                                    integer (multiple of 4)
66  *
67  * RETURN:      The converted Ascii character
68  *
69  * DESCRIPTION: Convert a hex digit to an Ascii character
70  *
71  ******************************************************************************/
72 
73 char
74 AcpiUtHexToAsciiChar (
75     UINT64                  Integer,
76     UINT32                  Position)
77 {
78     UINT64                  Index;
79 
80     AcpiUtShortShiftRight (Integer, Position, &Index);
81     return (AcpiGbl_HexToAscii[Index & 0xF]);
82 }
83 
84 
85 /*******************************************************************************
86  *
87  * FUNCTION:    AcpiUtAsciiToHexByte
88  *
89  * PARAMETERS:  TwoAsciiChars               - Pointer to two ASCII characters
90  *              ReturnByte                  - Where converted byte is returned
91  *
92  * RETURN:      Status and converted hex byte
93  *
94  * DESCRIPTION: Perform ascii-to-hex translation, exactly two ASCII characters
95  *              to a single converted byte value.
96  *
97  ******************************************************************************/
98 
99 ACPI_STATUS
100 AcpiUtAsciiToHexByte (
101     char                    *TwoAsciiChars,
102     UINT8                   *ReturnByte)
103 {
104 
105     /* Both ASCII characters must be valid hex digits */
106 
107     if (!isxdigit ((int) TwoAsciiChars[0]) ||
108         !isxdigit ((int) TwoAsciiChars[1]))
109     {
110         return (AE_BAD_HEX_CONSTANT);
111     }
112 
113     *ReturnByte =
114         AcpiUtAsciiCharToHex (TwoAsciiChars[1]) |
115         (AcpiUtAsciiCharToHex (TwoAsciiChars[0]) << 4);
116 
117     return (AE_OK);
118 }
119 
120 
121 /*******************************************************************************
122  *
123  * FUNCTION:    AcpiUtAsciiCharToHex
124  *
125  * PARAMETERS:  HexChar                 - Hex character in Ascii. Must be:
126  *                                        0-9 or A-F or a-f
127  *
128  * RETURN:      The binary value of the ascii/hex character
129  *
130  * DESCRIPTION: Perform ascii-to-hex translation
131  *
132  ******************************************************************************/
133 
134 UINT8
135 AcpiUtAsciiCharToHex (
136     int                     HexChar)
137 {
138 
139     /* Values 0-9 */
140 
141     if (HexChar <= '9')
142     {
143         return ((UINT8) (HexChar - '0'));
144     }
145 
146     /* Upper case A-F */
147 
148     if (HexChar <= 'F')
149     {
150         return ((UINT8) (HexChar - 0x37));
151     }
152 
153     /* Lower case a-f */
154 
155     return ((UINT8) (HexChar - 0x57));
156 }
157