ShellPkg : Cache the environment variable into memory to enhance

[mirror_edk2.git] / ShellPkg / Application / Shell / ShellEnvVar.c

/** @file\r
  function declarations for shell environment functions.\r
\r
  Copyright (c) 2009 - 2016, 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 "Shell.h"\r
\r
#define INIT_NAME_BUFFER_SIZE  128\r
#define INIT_DATA_BUFFER_SIZE  1024\r
\r
//\r
// The list is used to cache the environment variables.\r
//\r
ENV_VAR_LIST                   gShellEnvVarList;\r
\r
/**\r
  Reports whether an environment variable is Volatile or Non-Volatile.\r
\r
  @param EnvVarName             The name of the environment variable in question\r
\r
  @retval TRUE                  This environment variable is Volatile\r
  @retval FALSE                 This environment variable is NON-Volatile\r
**/\r
BOOLEAN\r
EFIAPI\r
IsVolatileEnv (\r
  IN CONST CHAR16 *EnvVarName\r
  )\r
{\r
  EFI_STATUS  Status;\r
  UINTN       Size;\r
  VOID        *Buffer;\r
  UINT32      Attribs;\r
\r
  Size = 0;\r
  Buffer = NULL;\r
\r
  //\r
  // get the variable\r
  //\r
  Status = gRT->GetVariable((CHAR16*)EnvVarName,\r
                            &gShellVariableGuid,\r
                            &Attribs,\r
                            &Size,\r
                            Buffer);\r
  if (Status == EFI_BUFFER_TOO_SMALL) {\r
    Buffer = AllocateZeroPool(Size);\r
    ASSERT(Buffer != NULL);\r
    Status = gRT->GetVariable((CHAR16*)EnvVarName,\r
                              &gShellVariableGuid,\r
                              &Attribs,\r
                              &Size,\r
                              Buffer);\r
    FreePool(Buffer);\r
  }\r
  //\r
  // not found means volatile\r
  //\r
  if (Status == EFI_NOT_FOUND) {\r
    return (TRUE);\r
  }\r
  ASSERT_EFI_ERROR(Status);\r
\r
  //\r
  // check for the Non Volatile bit\r
  //\r
  if ((Attribs & EFI_VARIABLE_NON_VOLATILE) == EFI_VARIABLE_NON_VOLATILE) {\r
    return (FALSE);\r
  }\r
\r
  //\r
  // everything else is volatile\r
  //\r
  return (TRUE);\r
}\r
\r
/**\r
  free function for ENV_VAR_LIST objects.\r
\r
  @param[in] List               The pointer to pointer to list.\r
**/\r
VOID\r
EFIAPI\r
FreeEnvironmentVariableList(\r
  IN LIST_ENTRY *List\r
  )\r
{\r
  ENV_VAR_LIST *Node;\r
\r
  ASSERT (List != NULL);\r
  if (List == NULL) {\r
    return;\r
  }\r
\r
  for ( Node = (ENV_VAR_LIST*)GetFirstNode(List)\r
      ; !IsListEmpty(List)\r
      ; Node = (ENV_VAR_LIST*)GetFirstNode(List)\r
     ){\r
    ASSERT(Node != NULL);\r
    RemoveEntryList(&Node->Link);\r
    if (Node->Key != NULL) {\r
      FreePool(Node->Key);\r
    }\r
    if (Node->Val != NULL) {\r
      FreePool(Node->Val);\r
    }\r
    FreePool(Node);\r
  }\r
}\r
\r
/**\r
  Creates a list of all Shell-Guid-based environment variables.\r
\r
  @param[in, out] ListHead       The pointer to pointer to LIST ENTRY object for\r
                                 storing this list.\r
\r
  @retval EFI_SUCCESS           the list was created sucessfully.\r
**/\r
EFI_STATUS\r
EFIAPI\r
GetEnvironmentVariableList(\r
  IN OUT LIST_ENTRY *ListHead\r
  )\r
{\r
  CHAR16            *VariableName;\r
  UINTN             NameSize;\r
  UINTN             NameBufferSize;\r
  EFI_STATUS        Status;\r
  EFI_GUID          Guid;\r
  UINTN             ValSize;\r
  UINTN             ValBufferSize;\r
  ENV_VAR_LIST      *VarList;\r
\r
  if (ListHead == NULL) {\r
    return (EFI_INVALID_PARAMETER);\r
  }\r
  \r
  Status = EFI_SUCCESS;\r
  \r
  ValBufferSize = INIT_DATA_BUFFER_SIZE;\r
  NameBufferSize = INIT_NAME_BUFFER_SIZE;\r
  VariableName = AllocateZeroPool(NameBufferSize);\r
  if (VariableName == NULL) {\r
    return (EFI_OUT_OF_RESOURCES);\r
  }\r
  *VariableName = CHAR_NULL;\r
\r
  while (!EFI_ERROR(Status)) {\r
    NameSize = NameBufferSize;\r
    Status = gRT->GetNextVariableName(&NameSize, VariableName, &Guid);\r
    if (Status == EFI_NOT_FOUND){\r
      Status = EFI_SUCCESS;\r
      break;\r
    } else if (Status == EFI_BUFFER_TOO_SMALL) {\r
      NameBufferSize = NameSize > NameBufferSize * 2 ? NameSize : NameBufferSize * 2;\r
      SHELL_FREE_NON_NULL(VariableName);\r
      VariableName = AllocateZeroPool(NameBufferSize);\r
      if (VariableName == NULL) {\r
        Status = EFI_OUT_OF_RESOURCES;\r
        break;\r
      }\r
      NameSize = NameBufferSize;\r
      Status = gRT->GetNextVariableName(&NameSize, VariableName, &Guid);\r
    }\r
    \r
    if (!EFI_ERROR(Status) && CompareGuid(&Guid, &gShellVariableGuid)){\r
      VarList = AllocateZeroPool(sizeof(ENV_VAR_LIST));\r
      if (VarList == NULL) {\r
        Status = EFI_OUT_OF_RESOURCES;\r
      } else {\r
        ValSize = ValBufferSize;\r
        VarList->Val = AllocateZeroPool(ValSize);\r
        if (VarList->Val == NULL) {\r
            SHELL_FREE_NON_NULL(VarList);\r
            Status = EFI_OUT_OF_RESOURCES;\r
            break;\r
        }\r
        Status = SHELL_GET_ENVIRONMENT_VARIABLE_AND_ATTRIBUTES(VariableName, &VarList->Atts, &ValSize, VarList->Val);\r
        if (Status == EFI_BUFFER_TOO_SMALL){\r
          ValBufferSize = ValSize > ValBufferSize * 2 ? ValSize : ValBufferSize * 2;\r
          SHELL_FREE_NON_NULL (VarList->Val);\r
          VarList->Val = AllocateZeroPool(ValBufferSize);\r
          if (VarList->Val == NULL) {\r
            SHELL_FREE_NON_NULL(VarList);\r
            Status = EFI_OUT_OF_RESOURCES;\r
            break;\r
          }\r
          \r
          ValSize = ValBufferSize;\r
          Status = SHELL_GET_ENVIRONMENT_VARIABLE_AND_ATTRIBUTES(VariableName, &VarList->Atts, &ValSize, VarList->Val);\r
        }\r
        if (!EFI_ERROR(Status)) {\r
          VarList->Key = AllocateCopyPool(StrSize(VariableName), VariableName);\r
          if (VarList->Key == NULL) {\r
            SHELL_FREE_NON_NULL(VarList->Val);\r
            SHELL_FREE_NON_NULL(VarList);\r
            Status = EFI_OUT_OF_RESOURCES;\r
          } else {\r
            InsertTailList(ListHead, &VarList->Link);\r
          }\r
        } else {\r
          SHELL_FREE_NON_NULL(VarList->Val);\r
          SHELL_FREE_NON_NULL(VarList);\r
        }\r
      } // if (VarList == NULL) ... else ...\r
    } // compare guid\r
  } // while\r
  SHELL_FREE_NON_NULL (VariableName);\r
\r
  if (EFI_ERROR(Status)) {\r
    FreeEnvironmentVariableList(ListHead);\r
  }\r
\r
  return (Status);\r
}\r
\r
/**\r
  Sets a list of all Shell-Guid-based environment variables.  this will\r
  also eliminate all existing shell environment variables (even if they\r
  are not on the list).\r
\r
  This function will also deallocate the memory from List.\r
\r
  @param[in] ListHead           The pointer to LIST_ENTRY from\r
                                GetShellEnvVarList().\r
\r
  @retval EFI_SUCCESS           the list was Set sucessfully.\r
**/\r
EFI_STATUS\r
EFIAPI\r
SetEnvironmentVariableList(\r
  IN LIST_ENTRY *ListHead\r
  )\r
{\r
  ENV_VAR_LIST      VarList;\r
  ENV_VAR_LIST      *Node;\r
  EFI_STATUS        Status;\r
  UINTN             Size;\r
\r
  InitializeListHead(&VarList.Link);\r
\r
  //\r
  // Delete all the current environment variables\r
  //\r
  Status = GetEnvironmentVariableList(&VarList.Link);\r
  ASSERT_EFI_ERROR(Status);\r
\r
  for ( Node = (ENV_VAR_LIST*)GetFirstNode(&VarList.Link)\r
      ; !IsNull(&VarList.Link, &Node->Link)\r
      ; Node = (ENV_VAR_LIST*)GetNextNode(&VarList.Link, &Node->Link)\r
     ){\r
    if (Node->Key != NULL) {\r
      Status = SHELL_DELETE_ENVIRONMENT_VARIABLE(Node->Key);\r
    }\r
    ASSERT_EFI_ERROR(Status);\r
  }\r
\r
  FreeEnvironmentVariableList(&VarList.Link);\r
\r
  //\r
  // set all the variables fron the list\r
  //\r
  for ( Node = (ENV_VAR_LIST*)GetFirstNode(ListHead)\r
      ; !IsNull(ListHead, &Node->Link)\r
      ; Node = (ENV_VAR_LIST*)GetNextNode(ListHead, &Node->Link)\r
     ){\r
    Size = StrSize(Node->Val);\r
    if (Node->Atts & EFI_VARIABLE_NON_VOLATILE) {\r
      Status = SHELL_SET_ENVIRONMENT_VARIABLE_NV(Node->Key, Size, Node->Val);\r
    } else {\r
      Status = SHELL_SET_ENVIRONMENT_VARIABLE_V (Node->Key, Size, Node->Val);\r
    }\r
    ASSERT_EFI_ERROR(Status);\r
  }\r
  FreeEnvironmentVariableList(ListHead);\r
\r
  return (Status);\r
}\r
\r
/**\r
  sets a list of all Shell-Guid-based environment variables.\r
\r
  @param Environment        Points to a NULL-terminated array of environment\r
                            variables with the format 'x=y', where x is the\r
                            environment variable name and y is the value.\r
\r
  @retval EFI_SUCCESS       The command executed successfully.\r
  @retval EFI_INVALID_PARAMETER The parameter is invalid.\r
  @retval EFI_OUT_OF_RESOURCES Out of resources.\r
\r
  @sa SetEnvironmentVariableList\r
**/\r
EFI_STATUS\r
EFIAPI\r
SetEnvironmentVariables(\r
  IN CONST CHAR16 **Environment\r
  )\r
{\r
  CONST CHAR16  *CurrentString;\r
  UINTN         CurrentCount;\r
  ENV_VAR_LIST  *VarList;\r
  ENV_VAR_LIST  *Node;\r
\r
  VarList = NULL;\r
\r
  if (Environment == NULL) {\r
    return (EFI_INVALID_PARAMETER);\r
  }\r
\r
  //\r
  // Build a list identical to the ones used for get/set list functions above\r
  //\r
  for ( CurrentCount = 0\r
      ;\r
      ; CurrentCount++\r
     ){\r
    CurrentString = Environment[CurrentCount];\r
    if (CurrentString == NULL) {\r
      break;\r
    }\r
    ASSERT(StrStr(CurrentString, L"=") != NULL);\r
    Node = AllocateZeroPool(sizeof(ENV_VAR_LIST));\r
    if (Node == NULL) {\r
      SetEnvironmentVariableList(&VarList->Link);\r
      return (EFI_OUT_OF_RESOURCES);\r
    }\r
\r
    Node->Key = AllocateZeroPool((StrStr(CurrentString, L"=") - CurrentString + 1) * sizeof(CHAR16));\r
    if (Node->Key == NULL) {\r
      SHELL_FREE_NON_NULL(Node);\r
      SetEnvironmentVariableList(&VarList->Link);\r
      return (EFI_OUT_OF_RESOURCES);\r
    }\r
\r
    //\r
    // Copy the string into the Key, leaving the last character allocated as NULL to terminate\r
    //\r
    StrnCpyS( Node->Key, \r
              StrStr(CurrentString, L"=") - CurrentString + 1, \r
              CurrentString,\r
              StrStr(CurrentString, L"=") - CurrentString\r
              );\r
\r
    //\r
    // ValueSize = TotalSize - already removed size - size for '=' + size for terminator (the last 2 items cancel each other)\r
    //\r
    Node->Val = AllocateCopyPool(StrSize(CurrentString) - StrSize(Node->Key), CurrentString + StrLen(Node->Key) + 1);\r
    if (Node->Val == NULL) {\r
      SHELL_FREE_NON_NULL(Node->Key);\r
      SHELL_FREE_NON_NULL(Node);\r
      SetEnvironmentVariableList(&VarList->Link);\r
      return (EFI_OUT_OF_RESOURCES);\r
    }\r
\r
    Node->Atts = EFI_VARIABLE_BOOTSERVICE_ACCESS;\r
\r
    if (VarList == NULL) {\r
      VarList = AllocateZeroPool(sizeof(ENV_VAR_LIST));\r
      if (VarList == NULL) {\r
        SHELL_FREE_NON_NULL(Node->Key);\r
        SHELL_FREE_NON_NULL(Node->Val);\r
        SHELL_FREE_NON_NULL(Node);\r
        return (EFI_OUT_OF_RESOURCES);\r
      }\r
      InitializeListHead(&VarList->Link);\r
    }\r
    InsertTailList(&VarList->Link, &Node->Link);\r
\r
  } // for loop\r
\r
  //\r
  // set this new list as the set of all environment variables.\r
  // this function also frees the memory and deletes all pre-existing\r
  // shell-guid based environment variables.\r
  //\r
  return (SetEnvironmentVariableList(&VarList->Link));\r
}\r
\r
/**\r
  Find an environment variable in the gShellEnvVarList.\r
\r
  @param Key        The name of the environment variable.\r
  @param Value      The value of the environment variable, the buffer\r
                    shoule be freed by the caller.\r
  @param ValueSize  The size in bytes of the environment variable\r
                    including the tailing CHAR_NELL.\r
  @param Atts       The attributes of the variable.\r
\r
  @retval EFI_SUCCESS       The command executed successfully.\r
  @retval EFI_NOT_FOUND     The environment variable is not found in\r
                            gShellEnvVarList.\r
\r
**/\r
EFI_STATUS\r
ShellFindEnvVarInList (\r
  IN  CONST CHAR16    *Key,\r
  OUT CHAR16          **Value,\r
  OUT UINTN           *ValueSize,\r
  OUT UINT32          *Atts OPTIONAL\r
  )\r
{\r
  ENV_VAR_LIST      *Node;\r
  \r
  if (Key == NULL || Value == NULL || ValueSize == NULL) {\r
    return SHELL_INVALID_PARAMETER;\r
  }\r
\r
  for ( Node = (ENV_VAR_LIST*)GetFirstNode(&gShellEnvVarList.Link)\r
      ; !IsNull(&gShellEnvVarList.Link, &Node->Link)\r
      ; Node = (ENV_VAR_LIST*)GetNextNode(&gShellEnvVarList.Link, &Node->Link)\r
     ){\r
    if (Node->Key != NULL && StrCmp(Key, Node->Key) == 0) {\r
      *Value      = AllocateCopyPool(StrSize(Node->Val), Node->Val);\r
      *ValueSize  = StrSize(Node->Val);\r
      if (Atts != NULL) {\r
        *Atts = Node->Atts;\r
      }\r
      return EFI_SUCCESS;\r
    }\r
  }\r
\r
  return EFI_NOT_FOUND;\r
}\r
\r
/**\r
  Add an environment variable into gShellEnvVarList.\r
\r
  @param Key        The name of the environment variable.\r
  @param Value      The value of environment variable.\r
  @param ValueSize  The size in bytes of the environment variable\r
                    including the tailing CHAR_NULL\r
  @param Atts       The attributes of the variable.\r
\r
**/\r
VOID\r
ShellAddEnvVarToList (\r
  IN CONST CHAR16     *Key,\r
  IN CONST CHAR16     *Value,\r
  IN UINTN            ValueSize,\r
  IN UINT32           Atts\r
  )\r
{\r
  ENV_VAR_LIST      *Node;\r
  \r
  if (Key == NULL || Value == NULL || ValueSize == 0) {\r
    return;\r
  }\r
\r
  //\r
  // Update the variable value if it exists in gShellEnvVarList.\r
  //\r
  for ( Node = (ENV_VAR_LIST*)GetFirstNode(&gShellEnvVarList.Link)\r
      ; !IsNull(&gShellEnvVarList.Link, &Node->Link)\r
      ; Node = (ENV_VAR_LIST*)GetNextNode(&gShellEnvVarList.Link, &Node->Link)\r
     ){\r
    if (Node->Key != NULL && StrCmp(Key, Node->Key) == 0) {\r
      Node->Atts = Atts;\r
      SHELL_FREE_NON_NULL(Node->Val);\r
      Node->Val  = AllocateZeroPool (ValueSize);\r
      ASSERT (Node->Val != NULL);\r
      CopyMem(Node->Val, Value, ValueSize);\r
      return;\r
    }\r
  }\r
\r
  //\r
  // If the environment varialbe key doesn't exist in list just insert\r
  // a new node.\r
  //\r
  Node = (ENV_VAR_LIST*)AllocateZeroPool (sizeof(ENV_VAR_LIST));\r
  ASSERT (Node != NULL);\r
  Node->Key = AllocateCopyPool(StrSize(Key), Key);\r
  ASSERT (Node->Key != NULL);\r
  Node->Val = AllocateCopyPool(ValueSize, Value);\r
  ASSERT (Node->Val != NULL);\r
  Node->Atts = Atts;\r
  InsertTailList(&gShellEnvVarList.Link, &Node->Link);\r
\r
  return;\r
}\r
\r
/**\r
  Remove a specified environment variable in gShellEnvVarList.\r
\r
  @param Key        The name of the environment variable.\r
  \r
  @retval EFI_SUCCESS       The command executed successfully.\r
  @retval EFI_NOT_FOUND     The environment variable is not found in\r
                            gShellEnvVarList.\r
**/\r
EFI_STATUS\r
ShellRemvoeEnvVarFromList (\r
  IN CONST CHAR16           *Key\r
  )\r
{\r
  ENV_VAR_LIST      *Node;\r
\r
  if (Key == NULL) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  for ( Node = (ENV_VAR_LIST*)GetFirstNode(&gShellEnvVarList.Link)\r
      ; !IsNull(&gShellEnvVarList.Link, &Node->Link)\r
      ; Node = (ENV_VAR_LIST*)GetNextNode(&gShellEnvVarList.Link, &Node->Link)\r
     ){\r
    if (Node->Key != NULL && StrCmp(Key, Node->Key) == 0) {\r
      SHELL_FREE_NON_NULL(Node->Key);\r
      SHELL_FREE_NON_NULL(Node->Val);\r
      RemoveEntryList(&Node->Link);\r
      SHELL_FREE_NON_NULL(Node);\r
      return EFI_SUCCESS;\r
    }\r
  }\r
\r
  return EFI_NOT_FOUND;\r
}\r
\r
/**\r
  Initialize the gShellEnvVarList and cache all Shell-Guid-based environment\r
  variables.\r
  \r
**/\r
EFI_STATUS\r
ShellInitEnvVarList (\r
  VOID\r
  )\r
{\r
  EFI_STATUS    Status;\r
\r
  InitializeListHead(&gShellEnvVarList.Link);\r
  Status = GetEnvironmentVariableList (&gShellEnvVarList.Link);\r
\r
  return Status;\r
}\r
\r
/**\r
  Destructe the gShellEnvVarList.\r
\r
**/\r
VOID\r
ShellFreeEnvVarList (\r
  VOID\r
  )\r
{\r
  FreeEnvironmentVariableList (&gShellEnvVarList.Link);\r
  InitializeListHead(&gShellEnvVarList.Link);\r
\r
  return;\r
}\r
\r