ShellPkg/Library/UefiShellCEntryLib/UefiShellCEntryLib.c

   1 /** @file
   2   Provides application point extension for "C" style main function
   3
   4   Copyright (c) 2009 - 2016, Intel Corporation. All rights reserved.<BR>
   5   This program and the accompanying materials
   6   are licensed and made available under the terms and conditions of the BSD License
   7   which accompanies this distribution.  The full text of the license may be found at
   8   http://opensource.org/licenses/bsd-license.php
   9
  10   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13 **/
  14
  15 #include <Base.h>
  16
  17 #include <Protocol/SimpleFileSystem.h>
  18 #include <Protocol/LoadedImage.h>
  19 #include <Protocol/EfiShellInterface.h>
  20 #include <Protocol/ShellParameters.h>
  21
  22 #include <Library/ShellCEntryLib.h>
  23 #include <Library/DebugLib.h>
  24
  25 /**
  26   UEFI entry point for an application that will in turn call the
  27   ShellAppMain function which has parameters similar to a standard C
  28   main function.
  29
  30   An application that uses UefiShellCEntryLib must have a ShellAppMain
  31   function as prototyped in Include/Library/ShellCEntryLib.h.
  32
  33   Note that the Shell uses POSITIVE integers for error values, while UEFI
  34   uses NEGATIVE values.  If the application is to be used within a script,
  35   it needs to return one of the SHELL_STATUS values defined in Protocol/Shell.h.
  36
  37   @param  ImageHandle  The image handle of the UEFI Application.
  38   @param  SystemTable  A pointer to the EFI System Table.
  39
  40   @retval  EFI_SUCCESS               The application exited normally.
  41   @retval  Other                     An error occurred.
  42
  43 **/
  44 EFI_STATUS
  45 EFIAPI
  46 ShellCEntryLib (
  47   IN EFI_HANDLE        ImageHandle,
  48   IN EFI_SYSTEM_TABLE  *SystemTable
  49   )
  50 {
  51   INTN                           ReturnFromMain;
  52   EFI_SHELL_PARAMETERS_PROTOCOL *EfiShellParametersProtocol;
  53   EFI_SHELL_INTERFACE           *EfiShellInterface;
  54   EFI_STATUS                    Status;
  55
  56   ReturnFromMain = -1;
  57   EfiShellParametersProtocol = NULL;
  58   EfiShellInterface = NULL;
  59
  60   Status = SystemTable->BootServices->OpenProtocol(ImageHandle,
  61                              &gEfiShellParametersProtocolGuid,
  62                              (VOID **)&EfiShellParametersProtocol,
  63                              ImageHandle,
  64                              NULL,
  65                              EFI_OPEN_PROTOCOL_GET_PROTOCOL
  66                             );
  67   if (!EFI_ERROR(Status)) {
  68     //
  69     // use shell 2.0 interface
  70     //
  71     ReturnFromMain = ShellAppMain (
  72                        EfiShellParametersProtocol->Argc,
  73                        EfiShellParametersProtocol->Argv
  74                       );
  75   } else {
  76     //
  77     // try to get shell 1.0 interface instead.
  78     //
  79     Status = SystemTable->BootServices->OpenProtocol(ImageHandle,
  80                                &gEfiShellInterfaceGuid,
  81                                (VOID **)&EfiShellInterface,
  82                                ImageHandle,
  83                                NULL,
  84                                EFI_OPEN_PROTOCOL_GET_PROTOCOL
  85                               );
  86     if (!EFI_ERROR(Status)) {
  87       //
  88       // use shell 1.0 interface
  89       //
  90       ReturnFromMain = ShellAppMain (
  91                          EfiShellInterface->Argc,
  92                          EfiShellInterface->Argv
  93                         );
  94     } else {
  95       ASSERT(FALSE);
  96     }
  97   }
  98   return ReturnFromMain;
  99 }