MdeModulePkg: Replace BSD License with BSD+Patent License

[mirror_edk2.git] / MdeModulePkg / Core / Dxe / Library / Library.c

/** @file\r
  DXE Core library services.\r
\r
Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>\r
SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
#include "DxeMain.h"\r
\r
//\r
// Lock Stuff\r
//\r
/**\r
  Initialize a basic mutual exclusion lock.   Each lock\r
  provides mutual exclusion access at it's task priority\r
  level.  Since there is no-premption (at any TPL) or\r
  multiprocessor support, acquiring the lock only consists\r
  of raising to the locks TPL.\r
\r
  @param  Lock               The EFI_LOCK structure to initialize\r
\r
  @retval EFI_SUCCESS        Lock Owned.\r
  @retval EFI_ACCESS_DENIED  Reentrant Lock Acquisition, Lock not Owned.\r
\r
**/\r
EFI_STATUS\r
CoreAcquireLockOrFail (\r
  IN EFI_LOCK  *Lock\r
  )\r
{\r
  ASSERT (Lock != NULL);\r
  ASSERT (Lock->Lock != EfiLockUninitialized);\r
\r
  if (Lock->Lock == EfiLockAcquired) {\r
    //\r
    // Lock is already owned, so bail out\r
    //\r
    return EFI_ACCESS_DENIED;\r
  }\r
\r
  Lock->OwnerTpl = CoreRaiseTpl (Lock->Tpl);\r
\r
  Lock->Lock = EfiLockAcquired;\r
  return EFI_SUCCESS;\r
}\r
\r
\r
\r
/**\r
  Raising to the task priority level of the mutual exclusion\r
  lock, and then acquires ownership of the lock.\r
\r
  @param  Lock               The lock to acquire\r
\r
  @return Lock owned\r
\r
**/\r
VOID\r
CoreAcquireLock (\r
  IN EFI_LOCK  *Lock\r
  )\r
{\r
  ASSERT (Lock != NULL);\r
  ASSERT (Lock->Lock == EfiLockReleased);\r
\r
  Lock->OwnerTpl = CoreRaiseTpl (Lock->Tpl);\r
  Lock->Lock     = EfiLockAcquired;\r
}\r
\r
\r
\r
/**\r
  Releases ownership of the mutual exclusion lock, and\r
  restores the previous task priority level.\r
\r
  @param  Lock               The lock to release\r
\r
  @return Lock unowned\r
\r
**/\r
VOID\r
CoreReleaseLock (\r
  IN EFI_LOCK  *Lock\r
  )\r
{\r
  EFI_TPL Tpl;\r
\r
  ASSERT (Lock != NULL);\r
  ASSERT (Lock->Lock == EfiLockAcquired);\r
\r
  Tpl = Lock->OwnerTpl;\r
\r
  Lock->Lock = EfiLockReleased;\r
\r
  CoreRestoreTpl (Tpl);\r
}\r
\r
\r
\r