MdeModulePkg/Library/UefiHiiLib/HiiLanguage.c

   1 /** @file
   2   Language related HII Library implementation.
   3
   4   Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
   5   SPDX-License-Identifier: BSD-2-Clause-Patent
   6
   7 **/
   8
   9
  10 #include "InternalHiiLib.h"
  11
  12 /**
  13   Retrieves a pointer to the a Null-terminated ASCII string containing the list
  14   of languages that an HII handle in the HII Database supports.  The returned
  15   string is allocated using AllocatePool().  The caller is responsible for freeing
  16   the returned string using FreePool().  The format of the returned string follows
  17   the language format assumed the HII Database.
  18
  19   If HiiHandle is NULL, then ASSERT().
  20
  21   @param[in]  HiiHandle  A handle that was previously registered in the HII Database.
  22
  23   @retval NULL   HiiHandle is not registered in the HII database
  24   @retval NULL   There are not enough resources available to retrieve the supported
  25                  languages.
  26   @retval NULL   The list of supported languages could not be retrieved.
  27   @retval Other  A pointer to the Null-terminated ASCII string of supported languages.
  28
  29 **/
  30 CHAR8 *
  31 EFIAPI
  32 HiiGetSupportedLanguages (
  33   IN EFI_HII_HANDLE           HiiHandle
  34   )
  35 {
  36   EFI_STATUS  Status;
  37   UINTN       LanguageSize;
  38   CHAR8       TempSupportedLanguages;
  39   CHAR8       *SupportedLanguages;
  40
  41   ASSERT (HiiHandle != NULL);
  42
  43   //
  44   // Retrieve the size required for the supported languages buffer.
  45   //
  46   LanguageSize = 0;
  47   Status = gHiiString->GetLanguages (gHiiString, HiiHandle, &TempSupportedLanguages, &LanguageSize);
  48
  49   //
  50   // If GetLanguages() returns EFI_SUCCESS for a zero size,
  51   // then there are no supported languages registered for HiiHandle.  If GetLanguages()
  52   // returns an error other than EFI_BUFFER_TOO_SMALL, then HiiHandle is not present
  53   // in the HII Database
  54   //
  55   if (Status != EFI_BUFFER_TOO_SMALL) {
  56     //
  57     // Return NULL if the size can not be retrieved, or if HiiHandle is not in the HII Database
  58     //
  59     return NULL;
  60   }
  61
  62   //
  63   // Allocate the supported languages buffer.
  64   //
  65   SupportedLanguages = AllocateZeroPool (LanguageSize);
  66   if (SupportedLanguages == NULL) {
  67     //
  68     // Return NULL if allocation fails.
  69     //
  70     return NULL;
  71   }
  72
  73   //
  74   // Retrieve the supported languages string
  75   //
  76   Status = gHiiString->GetLanguages (gHiiString, HiiHandle, SupportedLanguages, &LanguageSize);
  77   if (EFI_ERROR (Status)) {
  78     //
  79     // Free the buffer and return NULL if the supported languages can not be retrieved.
  80     //
  81     FreePool (SupportedLanguages);
  82     return NULL;
  83   }
  84
  85   //
  86   // Return the Null-terminated ASCII string of supported languages
  87   //
  88   return SupportedLanguages;
  89 }
  90