ShellPkg/Dp: Add null pointer check

[mirror_edk2.git] / ShellPkg / Library / UefiShellLevel3CommandsLib / Echo.c

/** @file\r
  Main file for Echo shell level 3 function.\r
\r
  (C) Copyright 2015 Hewlett-Packard Development Company, L.P.<BR>\r
  Copyright (c) 2009 - 2012, Intel Corporation. All rights reserved. <BR>\r
  This program and the accompanying materials\r
  are licensed and made available under the terms and conditions of the BSD License\r
  which accompanies this distribution.  The full text of the license may be found at\r
  http://opensource.org/licenses/bsd-license.php\r
\r
  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
\r
**/\r
\r
#include "UefiShellLevel3CommandsLib.h"\r
\r
#include <Library/ShellLib.h>\r
\r
STATIC CONST SHELL_PARAM_ITEM ParamList[] = {\r
  {L"-on", TypeFlag},\r
  {L"-off", TypeFlag},\r
  {NULL, TypeMax}\r
  };\r
\r
/**\r
  Function for 'echo' command.\r
\r
  @param[in] ImageHandle  Handle to the Image (NULL if Internal).\r
  @param[in] SystemTable  Pointer to the System Table (NULL if Internal).\r
**/\r
SHELL_STATUS\r
EFIAPI\r
ShellCommandRunEcho (\r
  IN EFI_HANDLE        ImageHandle,\r
  IN EFI_SYSTEM_TABLE  *SystemTable\r
  )\r
{\r
  EFI_STATUS          Status;\r
  LIST_ENTRY          *Package;\r
  SHELL_STATUS        ShellStatus;\r
  UINTN               ParamCount;\r
  CHAR16              *ProblemParam;\r
  UINTN               Size;\r
  CHAR16              *PrintString;\r
\r
  Size                = 0;\r
  ProblemParam        = NULL;\r
  PrintString         = NULL;\r
  ShellStatus         = SHELL_SUCCESS;\r
\r
  //\r
  // initialize the shell lib (we must be in non-auto-init...)\r
  //\r
  Status = ShellInitialize();\r
  ASSERT_EFI_ERROR(Status);\r
\r
  //\r
  // parse the command line\r
  //\r
  Status = ShellCommandLineParseEx (ParamList, &Package, &ProblemParam, TRUE, TRUE);\r
  if (EFI_ERROR(Status)) {\r
    if (Status == EFI_VOLUME_CORRUPTED && ProblemParam != NULL) {\r
      ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_GEN_PROBLEM), gShellLevel3HiiHandle, L"echo", ProblemParam);  \r
      FreePool(ProblemParam);\r
      ShellStatus = SHELL_INVALID_PARAMETER;\r
    } else {\r
      ASSERT(FALSE);\r
    }\r
  } else {\r
    //\r
    // check for "-?"\r
    //\r
    if (ShellCommandLineGetFlag(Package, L"-?")) {\r
      ASSERT(FALSE);\r
    }\r
    if (ShellCommandLineGetFlag(Package, L"-on")) {\r
      //\r
      // Turn it on\r
      //\r
      ShellCommandSetEchoState(TRUE);\r
    } else if (ShellCommandLineGetFlag(Package, L"-off")) {\r
      //\r
      // turn it off\r
      //\r
      ShellCommandSetEchoState(FALSE);\r
    } else if (ShellCommandLineGetRawValue(Package, 1) == NULL) {\r
      //\r
      // output its current state\r
      //\r
      if (ShellCommandGetEchoState()) {\r
        ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_ECHO_ON), gShellLevel3HiiHandle);\r
      } else {\r
        ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_ECHO_OFF), gShellLevel3HiiHandle);\r
      }\r
    } else {\r
      //\r
      // print the line\r
      //\r
      for ( ParamCount = 1\r
          ; ShellCommandLineGetRawValue(Package, ParamCount) != NULL\r
          ; ParamCount++\r
         ) {\r
        StrnCatGrow(&PrintString, &Size, ShellCommandLineGetRawValue(Package, ParamCount), 0);\r
        if (ShellCommandLineGetRawValue(Package, ParamCount+1) != NULL) {\r
          StrnCatGrow(&PrintString, &Size, L" ", 0);\r
        } \r
      }\r
      ShellPrintEx(-1, -1, L"%s\r\n", PrintString);\r
      SHELL_FREE_NON_NULL(PrintString);\r
    }\r
\r
    //\r
    // free the command line package\r
    //\r
    ShellCommandLineFreeVarList (Package);\r
  }\r
\r
  return (ShellStatus);\r
}\r
\r