drivers/acpi/acpica/utascii.c

   1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
   2 /******************************************************************************
   3  *
   4  * Module Name: utascii - Utility ascii functions
   5  *
   6  * Copyright (C) 2000 - 2020, Intel Corp.
   7  *
   8  *****************************************************************************/
   9
  10 #include <acpi/acpi.h>
  11 #include "accommon.h"
  12
  13 /*******************************************************************************
  14  *
  15  * FUNCTION:    acpi_ut_valid_nameseg
  16  *
  17  * PARAMETERS:  name            - The name or table signature to be examined.
  18  *                                Four characters, does not have to be a
  19  *                                NULL terminated string.
  20  *
  21  * RETURN:      TRUE if signature is has 4 valid ACPI characters
  22  *
  23  * DESCRIPTION: Validate an ACPI table signature.
  24  *
  25  ******************************************************************************/
  26
  27 u8 acpi_ut_valid_nameseg(char *name)
  28 {
  29         u32 i;
  30
  31         /* Validate each character in the signature */
  32
  33         for (i = 0; i < ACPI_NAMESEG_SIZE; i++) {
  34                 if (!acpi_ut_valid_name_char(name[i], i)) {
  35                         return (FALSE);
  36                 }
  37         }
  38
  39         return (TRUE);
  40 }
  41
  42 /*******************************************************************************
  43  *
  44  * FUNCTION:    acpi_ut_valid_name_char
  45  *
  46  * PARAMETERS:  char            - The character to be examined
  47  *              position        - Byte position (0-3)
  48  *
  49  * RETURN:      TRUE if the character is valid, FALSE otherwise
  50  *
  51  * DESCRIPTION: Check for a valid ACPI character. Must be one of:
  52  *              1) Upper case alpha
  53  *              2) numeric
  54  *              3) underscore
  55  *
  56  *              We allow a '!' as the last character because of the ASF! table
  57  *
  58  ******************************************************************************/
  59
  60 u8 acpi_ut_valid_name_char(char character, u32 position)
  61 {
  62
  63         if (!((character >= 'A' && character <= 'Z') ||
  64               (character >= '0' && character <= '9') || (character == '_'))) {
  65
  66                 /* Allow a '!' in the last position */
  67
  68                 if (character == '!' && position == 3) {
  69                         return (TRUE);
  70                 }
  71
  72                 return (FALSE);
  73         }
  74
  75         return (TRUE);
  76 }
  77
  78 /*******************************************************************************
  79  *
  80  * FUNCTION:    acpi_ut_check_and_repair_ascii
  81  *
  82  * PARAMETERS:  name                - Ascii string
  83  *              count               - Number of characters to check
  84  *
  85  * RETURN:      None
  86  *
  87  * DESCRIPTION: Ensure that the requested number of characters are printable
  88  *              Ascii characters. Sets non-printable and null chars to <space>.
  89  *
  90  ******************************************************************************/
  91
  92 void acpi_ut_check_and_repair_ascii(u8 *name, char *repaired_name, u32 count)
  93 {
  94         u32 i;
  95
  96         for (i = 0; i < count; i++) {
  97                 repaired_name[i] = (char)name[i];
  98
  99                 if (!name[i]) {
 100                         return;
 101                 }
 102                 if (!isprint(name[i])) {
 103                         repaired_name[i] = ' ';
 104                 }
 105         }
 106 }