Updating with new functions and adding "C" style entrypoint library with example application.

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@8564 6f19259b-4bc3-4df7-8a09-765794883524

ShellPkg/Library/UefiShellCEntryLib/UefiShellCEntryLib.c

@@ -0,0 +1,82 @@
+/** @file
+  Provides application point extension for "C" style main funciton 
+
+Copyright (c) 2009, Intel Corporation
+All rights reserved. This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution.  The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include <Base.h>
+
+#include <Protocol/SimpleFileSystem.h>
+#include <Protocol/EfiShellInterface.h>
+#include <Protocol/EfiShellParameters.h>
+
+#include <Library/DebugLib.h>
+
+INT32 
+EFIAPI 
+main(
+  UINTN Argc, 
+  CHAR16 **Argv
+);
+
+EFI_STATUS
+EFIAPI
+ShellCEntryLib(
+  IN EFI_HANDLE        ImageHandle,
+  IN EFI_SYSTEM_TABLE  *SystemTable
+  ){
+  INT32                         ReturnFromMain;
+  EFI_SHELL_PARAMETERS_PROTOCOL *EfiShellParametersProtocol;
+  EFI_SHELL_INTERFACE           *EfiShellInterface;
+  EFI_STATUS                    Status;
+
+  ReturnFromMain = -1;
+  EfiShellParametersProtocol = NULL;
+  EfiShellInterface = NULL;
+
+  Status = SystemTable->BootServices->OpenProtocol(ImageHandle, 
+                             &gEfiShellParametersProtocolGuid,
+                             (VOID **)&EfiShellParametersProtocol,
+                             ImageHandle,
+                             NULL,
+                             EFI_OPEN_PROTOCOL_GET_PROTOCOL
+                             );
+  if (!EFI_ERROR(Status)) {
+    //
+    // use shell 2.0 interface
+    //
+    ReturnFromMain = main(EfiShellInterface->Argc, EfiShellInterface->Argv);
+  } else {
+    //
+    // try to get shell 1.0 interface instead.
+    //
+    Status = SystemTable->BootServices->OpenProtocol(ImageHandle, 
+                               &gEfiShellInterfaceGuid,
+                               (VOID **)&EfiShellInterface,
+                               ImageHandle,
+                               NULL,
+                               EFI_OPEN_PROTOCOL_GET_PROTOCOL
+                               );
+    if (!EFI_ERROR(Status)) {
+      //
+      // use shell 1.0 interface
+      // 
+      ReturnFromMain = main(EfiShellParametersProtocol->Argc, EfiShellParametersProtocol->Argv);
+    } else {
+      ASSERT(FALSE);
+    }
+  }
+  if (ReturnFromMain == 0) {
+    return (EFI_SUCCESS);
+  } else {
+    return (EFI_UNSUPPORTED);
+  }
+}