MdeModulePkg/Universal/BdsDxe/Language.c

   1 /** @file
   2   Language settings
   3
   4 Copyright (c) 2004 - 2018, Intel Corporation. All rights reserved.<BR>
   5 SPDX-License-Identifier: BSD-2-Clause-Patent
   6
   7 **/
   8
   9 #include "Bds.h"
  10 #define ISO_639_2_ENTRY_SIZE 3
  11
  12 /**
  13   Check if lang is in supported language codes according to language string.
  14
  15   This code is used to check if lang is in in supported language codes. It can handle
  16   RFC4646 and ISO639 language tags.
  17   In ISO639 language tags, take 3-characters as a delimitation to find matched string.
  18   In RFC4646 language tags, take semicolon as a delimitation to find matched string.
  19
  20   For example:
  21     SupportedLang  = "engfraengfra"
  22     Iso639Language = TRUE
  23     Lang           = "eng", the return value is "TRUE", or
  24     Lang           = "chs", the return value is "FALSE".
  25   Another example:
  26     SupportedLang  = "en;fr;en-US;fr-FR"
  27     Iso639Language = FALSE
  28     Lang           = "en", the return value is "TRUE", or
  29     Lang           = "zh", the return value is "FALSE".
  30
  31   @param  SupportedLang               Platform supported language codes.
  32   @param  Lang                        Configured language.
  33   @param  Iso639Language              A bool value to signify if the handler is operated on ISO639 or RFC4646.
  34
  35   @retval TRUE  lang is in supported language codes.
  36   @retval FALSE lang is not in supported language codes.
  37
  38 **/
  39 BOOLEAN
  40 IsLangInSupportedLangCodes(
  41   IN  CHAR8            *SupportedLang,
  42   IN  CHAR8            *Lang,
  43   IN  BOOLEAN          Iso639Language
  44   )
  45 {
  46   UINTN    Index;
  47   UINTN    CompareLength;
  48   UINTN    LanguageLength;
  49
  50   if (Iso639Language) {
  51     CompareLength = ISO_639_2_ENTRY_SIZE;
  52     for (Index = 0; Index < AsciiStrLen (SupportedLang); Index += CompareLength) {
  53       if (AsciiStrnCmp (Lang, SupportedLang + Index, CompareLength) == 0) {
  54         //
  55         // Successfully find the Lang string in SupportedLang string.
  56         //
  57         return TRUE;
  58       }
  59     }
  60     return FALSE;
  61   } else {
  62     //
  63     // Compare RFC4646 language code
  64     //
  65     for (LanguageLength = 0; Lang[LanguageLength] != '\0'; LanguageLength++);
  66
  67     for (; *SupportedLang != '\0'; SupportedLang += CompareLength) {
  68       //
  69       // Skip ';' characters in SupportedLang
  70       //
  71       for (; *SupportedLang != '\0' && *SupportedLang == ';'; SupportedLang++);
  72       //
  73       // Determine the length of the next language code in SupportedLang
  74       //
  75       for (CompareLength = 0; SupportedLang[CompareLength] != '\0' && SupportedLang[CompareLength] != ';'; CompareLength++);
  76
  77       if ((CompareLength == LanguageLength) &&
  78           (AsciiStrnCmp (Lang, SupportedLang, CompareLength) == 0)) {
  79         //
  80         // Successfully find the Lang string in SupportedLang string.
  81         //
  82         return TRUE;
  83       }
  84     }
  85     return FALSE;
  86   }
  87 }
  88
  89 /**
  90   Initialize Lang or PlatformLang variable, if Lang or PlatformLang variable is not found,
  91   or it has been set to an unsupported value(not one of platform supported language codes),
  92   set the default language code to it.
  93
  94   @param  LangName                    Language name, L"Lang" or L"PlatformLang".
  95   @param  SupportedLang               Platform supported language codes.
  96   @param  DefaultLang                 Default language code.
  97   @param  Iso639Language              A bool value to signify if the handler is operated on ISO639 or RFC4646,
  98                                       TRUE for L"Lang" LangName or FALSE for L"PlatformLang" LangName.
  99
 100 **/
 101 VOID
 102 InitializeLangVariable (
 103   IN CHAR16     *LangName,
 104   IN CHAR8      *SupportedLang,
 105   IN CHAR8      *DefaultLang,
 106   IN BOOLEAN    Iso639Language
 107   )
 108 {
 109   CHAR8       *Lang;
 110
 111   //
 112   // Find current Lang or PlatformLang from EFI Variable.
 113   //
 114   GetEfiGlobalVariable2 (LangName, (VOID **) &Lang, NULL);
 115
 116   //
 117   // If Lang or PlatformLang variable is not found,
 118   // or it has been set to an unsupported value(not one of the supported language codes),
 119   // set the default language code to it.
 120   //
 121   if ((Lang == NULL) || !IsLangInSupportedLangCodes (SupportedLang, Lang, Iso639Language)) {
 122     //
 123     // The default language code should be one of the supported language codes.
 124     //
 125     ASSERT (IsLangInSupportedLangCodes (SupportedLang, DefaultLang, Iso639Language));
 126     BdsDxeSetVariableAndReportStatusCodeOnError (
 127       LangName,
 128       &gEfiGlobalVariableGuid,
 129       EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS,
 130       AsciiStrSize (DefaultLang),
 131       DefaultLang
 132       );
 133   }
 134
 135   if (Lang != NULL) {
 136     FreePool (Lang);
 137   }
 138 }
 139
 140 /**
 141   Determine the current language that will be used
 142   based on language related EFI Variables.
 143
 144   @param LangCodesSettingRequired - If required to set LangCodes variable
 145
 146 **/
 147 VOID
 148 InitializeLanguage (
 149   BOOLEAN LangCodesSettingRequired
 150   )
 151 {
 152   EFI_STATUS  Status;
 153   CHAR8       *LangCodes;
 154   CHAR8       *PlatformLangCodes;
 155
 156   LangCodes = (CHAR8 *)PcdGetPtr (PcdUefiVariableDefaultLangCodes);
 157   PlatformLangCodes = (CHAR8 *)PcdGetPtr (PcdUefiVariableDefaultPlatformLangCodes);
 158   if (LangCodesSettingRequired) {
 159     if (!FeaturePcdGet (PcdUefiVariableDefaultLangDeprecate)) {
 160       //
 161       // UEFI 2.1 depricated this variable so we support turning it off
 162       //
 163       Status = gRT->SetVariable (
 164                       L"LangCodes",
 165                       &gEfiGlobalVariableGuid,
 166                       EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS,
 167                       AsciiStrSize (LangCodes),
 168                       LangCodes
 169                       );
 170       //
 171       // Platform needs to make sure setting volatile variable before calling 3rd party code shouldn't fail.
 172       //
 173       ASSERT_EFI_ERROR(Status);
 174     }
 175
 176     Status = gRT->SetVariable (
 177                     L"PlatformLangCodes",
 178                     &gEfiGlobalVariableGuid,
 179                     EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS,
 180                     AsciiStrSize (PlatformLangCodes),
 181                     PlatformLangCodes
 182                     );
 183     //
 184     // Platform needs to make sure setting volatile variable before calling 3rd party code shouldn't fail.
 185     //
 186     ASSERT_EFI_ERROR(Status);
 187   }
 188
 189   if (!FeaturePcdGet (PcdUefiVariableDefaultLangDeprecate)) {
 190     //
 191     // UEFI 2.1 depricated this variable so we support turning it off
 192     //
 193     InitializeLangVariable (L"Lang", LangCodes, (CHAR8 *) PcdGetPtr (PcdUefiVariableDefaultLang), TRUE);
 194   }
 195   InitializeLangVariable (L"PlatformLang", PlatformLangCodes, (CHAR8 *) PcdGetPtr (PcdUefiVariableDefaultPlatformLang), FALSE);
 196 }