1 /****************************************************************************** 2 * 3 * Module Name: uthex -- Hex/ASCII support functions 4 * 5 *****************************************************************************/ 6 7 /* 8 * Copyright (C) 2000 - 2018, 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/acpi.h> 45 #include "accommon.h" 46 47 #define _COMPONENT ACPI_COMPILER 48 ACPI_MODULE_NAME("uthex") 49 50 /* Hex to ASCII conversion table */ 51 static const char acpi_gbl_hex_to_ascii[] = { 52 '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 53 'E', 'F' 54 }; 55 56 /******************************************************************************* 57 * 58 * FUNCTION: acpi_ut_hex_to_ascii_char 59 * 60 * PARAMETERS: integer - Contains the hex digit 61 * position - bit position of the digit within the 62 * integer (multiple of 4) 63 * 64 * RETURN: The converted Ascii character 65 * 66 * DESCRIPTION: Convert a hex digit to an Ascii character 67 * 68 ******************************************************************************/ 69 70 char acpi_ut_hex_to_ascii_char(u64 integer, u32 position) 71 { 72 u64 index; 73 74 acpi_ut_short_shift_right(integer, position, &index); 75 return (acpi_gbl_hex_to_ascii[index & 0xF]); 76 } 77 78 /******************************************************************************* 79 * 80 * FUNCTION: acpi_ut_ascii_to_hex_byte 81 * 82 * PARAMETERS: two_ascii_chars - Pointer to two ASCII characters 83 * return_byte - Where converted byte is returned 84 * 85 * RETURN: Status and converted hex byte 86 * 87 * DESCRIPTION: Perform ascii-to-hex translation, exactly two ASCII characters 88 * to a single converted byte value. 89 * 90 ******************************************************************************/ 91 92 acpi_status acpi_ut_ascii_to_hex_byte(char *two_ascii_chars, u8 *return_byte) 93 { 94 95 /* Both ASCII characters must be valid hex digits */ 96 97 if (!isxdigit((int)two_ascii_chars[0]) || 98 !isxdigit((int)two_ascii_chars[1])) { 99 return (AE_BAD_HEX_CONSTANT); 100 } 101 102 *return_byte = 103 acpi_ut_ascii_char_to_hex(two_ascii_chars[1]) | 104 (acpi_ut_ascii_char_to_hex(two_ascii_chars[0]) << 4); 105 106 return (AE_OK); 107 } 108 109 /******************************************************************************* 110 * 111 * FUNCTION: acpi_ut_ascii_char_to_hex 112 * 113 * PARAMETERS: hex_char - Hex character in Ascii. Must be: 114 * 0-9 or A-F or a-f 115 * 116 * RETURN: The binary value of the ascii/hex character 117 * 118 * DESCRIPTION: Perform ascii-to-hex translation 119 * 120 ******************************************************************************/ 121 122 u8 acpi_ut_ascii_char_to_hex(int hex_char) 123 { 124 125 /* Values 0-9 */ 126 127 if (hex_char <= '9') { 128 return ((u8)(hex_char - '0')); 129 } 130 131 /* Upper case A-F */ 132 133 if (hex_char <= 'F') { 134 return ((u8)(hex_char - 0x37)); 135 } 136 137 /* Lower case a-f */ 138 139 return ((u8)(hex_char - 0x57)); 140 } 141