Re: [edk2-devel] [PATCH v4 2/6] OvmfPkg: Add QemuFwCfgLibNull

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

Hi Rebecca,

On 4/24/20 8:29 PM, Rebecca Cran wrote:
> Add a null implementation library for QemuFwCfgLib, in order to
> support building PciHostBridgeLib for bhyve.
> 
> Signed-off-by: Rebecca Cran <rebecca@bsdio.com>
> ---
>   .../Library/QemuFwCfgLib/QemuFwCfgLibNull.inf |  37 ++++
>   OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgNull.c  | 209 ++++++++++++++++++
>   2 files changed, 246 insertions(+)
>   create mode 100644 OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLibNull.inf
>   create mode 100644 OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgNull.c
> 
> diff --git a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLibNull.inf b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLibNull.inf
> new file mode 100644
> index 0000000000..09f86c2b02
> --- /dev/null
> +++ b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgLibNull.inf
> @@ -0,0 +1,37 @@
> +## @file
> +#
> +#  Stateful, implicitly initialized fw_cfg library.
> +#
> +#  Copyright (C) 2013, Red Hat, Inc.
> +#  Copyright (c) 2008 - 2012, Intel Corporation. All rights reserved.<BR>
> +#  Copyright (c) 2017, AMD Incorporated. All rights reserved.<BR>
> +#
> +#  SPDX-License-Identifier: BSD-2-Clause-Patent
> +#
> +##
> +
> +[Defines]
> +  INF_VERSION                    = 0x00010005
> +  BASE_NAME                      = QemuFwCfgLibNull
> +  FILE_GUID                      = B9D1A1F2-01E2-4732-982D-C7F9ED51AC6B
> +  MODULE_TYPE                    = BASE
> +  VERSION_STRING                 = 1.0
> +  LIBRARY_CLASS                  = QemuFwCfgLib
> +
> +#
> +# The following information is for reference only and not required by the build tools.
> +#
> +#  VALID_ARCHITECTURES           = IA32 X64
> +#
> +
> +[Sources]
> +  QemuFwCfgLibInternal.h
> +  QemuFwCfgNull.c
> +
> +[Packages]
> +  MdePkg/MdePkg.dec
> +  MdeModulePkg/MdeModulePkg.dec
> +  OvmfPkg/OvmfPkg.dec
> +
> +[LibraryClasses]
> +  DebugLib
> diff --git a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgNull.c b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgNull.c
> new file mode 100644
> index 0000000000..e2cc5f3406
> --- /dev/null
> +++ b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgNull.c
> @@ -0,0 +1,209 @@
> +/** @file
> +
> +  Stateful and implicitly initialized fw_cfg library implementation.
> +
> +  Copyright (C) 2013, Red Hat, Inc.
> +  Copyright (c) 2011 - 2013, Intel Corporation. All rights reserved.<BR>
> +  Copyright (c) 2017, Advanced Micro Devices. All rights reserved.<BR>
> +
> +  SPDX-License-Identifier: BSD-2-Clause-Patent
> +**/
> +
> +#include <Uefi.h>
> +#include <Library/DebugLib.h>
> +#include <IndustryStandard/QemuFwCfg.h>

Don't you need <Library/QemuFwCfgLib.h>?

> +
> +/**
> +  Returns a boolean indicating if the firmware configuration interface
> +  is available or not.
> +
> +  This function may change fw_cfg state.
> +
> +  @retval    TRUE   The interface is available
> +  @retval    FALSE  The interface is not available
> +
> +**/
> +BOOLEAN
> +EFIAPI
> +QemuFwCfgIsAvailable (
> +  VOID
> +  )
> +{
> +  return FALSE;
> +}
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