xref: /openbmc/linux/drivers/acpi/acpica/utascii.c (revision bbecb07f)
1 /******************************************************************************
2  *
3  * Module Name: utascii - Utility ascii functions
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2017, 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 /*******************************************************************************
48  *
49  * FUNCTION:    acpi_ut_valid_nameseg
50  *
51  * PARAMETERS:  name            - The name or table signature to be examined.
52  *                                Four characters, does not have to be a
53  *                                NULL terminated string.
54  *
55  * RETURN:      TRUE if signature is has 4 valid ACPI characters
56  *
57  * DESCRIPTION: Validate an ACPI table signature.
58  *
59  ******************************************************************************/
60 
61 u8 acpi_ut_valid_nameseg(char *name)
62 {
63 	u32 i;
64 
65 	/* Validate each character in the signature */
66 
67 	for (i = 0; i < ACPI_NAME_SIZE; i++) {
68 		if (!acpi_ut_valid_name_char(name[i], i)) {
69 			return (FALSE);
70 		}
71 	}
72 
73 	return (TRUE);
74 }
75 
76 /*******************************************************************************
77  *
78  * FUNCTION:    acpi_ut_valid_name_char
79  *
80  * PARAMETERS:  char            - The character to be examined
81  *              position        - Byte position (0-3)
82  *
83  * RETURN:      TRUE if the character is valid, FALSE otherwise
84  *
85  * DESCRIPTION: Check for a valid ACPI character. Must be one of:
86  *              1) Upper case alpha
87  *              2) numeric
88  *              3) underscore
89  *
90  *              We allow a '!' as the last character because of the ASF! table
91  *
92  ******************************************************************************/
93 
94 u8 acpi_ut_valid_name_char(char character, u32 position)
95 {
96 
97 	if (!((character >= 'A' && character <= 'Z') ||
98 	      (character >= '0' && character <= '9') || (character == '_'))) {
99 
100 		/* Allow a '!' in the last position */
101 
102 		if (character == '!' && position == 3) {
103 			return (TRUE);
104 		}
105 
106 		return (FALSE);
107 	}
108 
109 	return (TRUE);
110 }
111 
112 /*******************************************************************************
113  *
114  * FUNCTION:    acpi_ut_check_and_repair_ascii
115  *
116  * PARAMETERS:  name                - Ascii string
117  *              count               - Number of characters to check
118  *
119  * RETURN:      None
120  *
121  * DESCRIPTION: Ensure that the requested number of characters are printable
122  *              Ascii characters. Sets non-printable and null chars to <space>.
123  *
124  ******************************************************************************/
125 
126 void acpi_ut_check_and_repair_ascii(u8 *name, char *repaired_name, u32 count)
127 {
128 	u32 i;
129 
130 	for (i = 0; i < count; i++) {
131 		repaired_name[i] = (char)name[i];
132 
133 		if (!name[i]) {
134 			return;
135 		}
136 		if (!isprint(name[i])) {
137 			repaired_name[i] = ' ';
138 		}
139 	}
140 }
141