drivers/acpi/acpica/utnonansi.c

   1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
   2 /*******************************************************************************
   3  *
   4  * Module Name: utnonansi - Non-ansi C library functions
   5  *
   6  ******************************************************************************/
   7
   8 #include <acpi/acpi.h>
   9 #include "accommon.h"
  10
  11 #define _COMPONENT          ACPI_UTILITIES
  12 ACPI_MODULE_NAME("utnonansi")
  13
  14 /*
  15  * Non-ANSI C library functions - strlwr, strupr, stricmp, and "safe"
  16  * string functions.
  17  */
  18 /*******************************************************************************
  19  *
  20  * FUNCTION:    acpi_ut_strlwr (strlwr)
  21  *
  22  * PARAMETERS:  src_string      - The source string to convert
  23  *
  24  * RETURN:      None
  25  *
  26  * DESCRIPTION: Convert a string to lowercase
  27  *
  28  ******************************************************************************/
  29 void acpi_ut_strlwr(char *src_string)
  30 {
  31         char *string;
  32
  33         ACPI_FUNCTION_ENTRY();
  34
  35         if (!src_string) {
  36                 return;
  37         }
  38
  39         /* Walk entire string, lowercasing the letters */
  40
  41         for (string = src_string; *string; string++) {
  42                 *string = (char)tolower((int)*string);
  43         }
  44 }
  45
  46 /*******************************************************************************
  47  *
  48  * FUNCTION:    acpi_ut_strupr (strupr)
  49  *
  50  * PARAMETERS:  src_string      - The source string to convert
  51  *
  52  * RETURN:      None
  53  *
  54  * DESCRIPTION: Convert a string to uppercase
  55  *
  56  ******************************************************************************/
  57
  58 void acpi_ut_strupr(char *src_string)
  59 {
  60         char *string;
  61
  62         ACPI_FUNCTION_ENTRY();
  63
  64         if (!src_string) {
  65                 return;
  66         }
  67
  68         /* Walk entire string, uppercasing the letters */
  69
  70         for (string = src_string; *string; string++) {
  71                 *string = (char)toupper((int)*string);
  72         }
  73 }
  74
  75 /******************************************************************************
  76  *
  77  * FUNCTION:    acpi_ut_stricmp (stricmp)
  78  *
  79  * PARAMETERS:  string1             - first string to compare
  80  *              string2             - second string to compare
  81  *
  82  * RETURN:      int that signifies string relationship. Zero means strings
  83  *              are equal.
  84  *
  85  * DESCRIPTION: Case-insensitive string compare. Implementation of the
  86  *              non-ANSI stricmp function.
  87  *
  88  ******************************************************************************/
  89
  90 int acpi_ut_stricmp(char *string1, char *string2)
  91 {
  92         int c1;
  93         int c2;
  94
  95         do {
  96                 c1 = tolower((int)*string1);
  97                 c2 = tolower((int)*string2);
  98
  99                 string1++;
 100                 string2++;
 101         }
 102         while ((c1 == c2) && (c1));
 103
 104         return (c1 - c2);
 105 }
 106
 107 #if defined (ACPI_DEBUGGER) || defined (ACPI_APPLICATION) || defined (ACPI_DEBUG_OUTPUT)
 108 /*******************************************************************************
 109  *
 110  * FUNCTION:    acpi_ut_safe_strcpy, acpi_ut_safe_strcat, acpi_ut_safe_strncat
 111  *
 112  * PARAMETERS:  Adds a "DestSize" parameter to each of the standard string
 113  *              functions. This is the size of the Destination buffer.
 114  *
 115  * RETURN:      TRUE if the operation would overflow the destination buffer.
 116  *
 117  * DESCRIPTION: Safe versions of standard Clib string functions. Ensure that
 118  *              the result of the operation will not overflow the output string
 119  *              buffer.
 120  *
 121  * NOTE:        These functions are typically only helpful for processing
 122  *              user input and command lines. For most ACPICA code, the
 123  *              required buffer length is precisely calculated before buffer
 124  *              allocation, so the use of these functions is unnecessary.
 125  *
 126  ******************************************************************************/
 127
 128 u8 acpi_ut_safe_strcpy(char *dest, acpi_size dest_size, char *source)
 129 {
 130
 131         if (strlen(source) >= dest_size) {
 132                 return (TRUE);
 133         }
 134
 135         strcpy(dest, source);
 136         return (FALSE);
 137 }
 138
 139 u8 acpi_ut_safe_strcat(char *dest, acpi_size dest_size, char *source)
 140 {
 141
 142         if ((strlen(dest) + strlen(source)) >= dest_size) {
 143                 return (TRUE);
 144         }
 145
 146         strcat(dest, source);
 147         return (FALSE);
 148 }
 149
 150 u8
 151 acpi_ut_safe_strncat(char *dest,
 152                      acpi_size dest_size,
 153                      char *source, acpi_size max_transfer_length)
 154 {
 155         acpi_size actual_transfer_length;
 156
 157         actual_transfer_length = ACPI_MIN(max_transfer_length, strlen(source));
 158
 159         if ((strlen(dest) + actual_transfer_length) >= dest_size) {
 160                 return (TRUE);
 161         }
 162
 163         strncat(dest, source, max_transfer_length);
 164         return (FALSE);
 165 }
 166
 167 void acpi_ut_safe_strncpy(char *dest, char *source, acpi_size dest_size)
 168 {
 169         /* Always terminate destination string */
 170
 171         strncpy(dest, source, dest_size);
 172         dest[dest_size - 1] = 0;
 173 }
 174
 175 #endif