StorPortRegistryRead function (storport.h)

Article
04/18/2022

The StorPortRegistryRead routine reads the registry data for the indicated device and value.

Syntax

BOOLEAN StorPortRegistryRead(
  PVOID  HwDeviceExtension,
  PUCHAR ValueName,
  ULONG  Global,
  ULONG  Type,
  PUCHAR Buffer,
  PULONG BufferLength
);

Parameters

HwDeviceExtension

A pointer to the hardware device extension. This is a per HBA storage area that the port driver allocates and initializes on behalf of the miniport driver. Miniport drivers usually store HBA-specific information in this extension, such as the state of the HBA and the mapped access ranges for the HBA. This area is available to the miniport driver immediately after the miniport driver calls StorPortInitialize. The port driver frees this memory when it removes the device. The miniport driver must be running at IRQL PASSIVE_LEVEL when it calls this routine.

ValueName

Pointer to a UCHAR that specifies the registry value name whose content is to be read.

Global

Indicates, when nonzero, that the port driver reads the contents of the registry value specified by ValueName under the Parameters\Device subkey. The values under the Device key apply to all adapters in the system. When Global is zero, the port driver reads the contents of the registry value specified by ValueName under the Parameters\Device(d) subkey, where (d) is a decimal value that corresponds to the port number of a particular adapter. In this case, the data retrieved is adapter-specific.

Type

Indicates the data type of registry value. This parameter must have one of the values in the following table.

Registry value data type	Meaning
REG_NONE	No data type specified.
REG_SZ	Indicates a NULL-terminated Unicode string.
REG_EXPAND_SZ	Indicates a NULL-terminated Unicode string that includes environment variables that must be expanded to obtain the complete string. For example, a path name might be stored as the following string: "%USERPROFILE%\Application Data ". In this example, the environment variable USERPROFILE must be expanded to obtain the actual pathname.
REG_BINARY	Indicates a raw binary data.
REG_DWORD	Indicates a 32-bit double word value.
REG_DWORD_LITTLE_ENDIAN	Indicates a 32-bit double word value, in little-endian order. This is identical to REG_DWORD.
REG_DWORD_BIG_ENDIAN	Indicates a 32-bit double word value, in big-endian order.
REG_LINK	Indicates a Unicode string containing a symbolic link.
REG_MULTI_SZ	Indicates a series of NULL-terminated strings.
REG_RESOURCE_LIST	Indicates that the registry value contains a list of hardware resources, also known as the "hardware resource map", that is stored under the HKEY_LOCAL_MACHINE\HARDWARE\ResourceMap hive.
REG_FULL_RESOURCE_DESCRIPTOR	Indicates that the registry value contains a description of hardware resources stored under the HKEY_LOCAL_MACHINE\HARDWARE\Description hive.
REG_RESOURCE_REQUIREMENTS_LIST	Indicates that the registry value contains a list of hardware resource requirements stored under the HKEY_LOCAL_MACHINE\HARDWARE\ResourceMap tree.
REG_QWORD	Indicates that the registry value contains a 64-bit number.
REG_QWORD_LITTLE_ENDIAN	Indicates that the registry value contains a 64-bit number. This is the same data type as REG_QWORD.

Buffer

Pointer to the buffer where the retrieved registry information is to be reported.

BufferLength

Pointer to a ULONG that contains the size, in bytes, of the registry data returned.

Return value

StorPortRegistryRead returns a Boolean value of TRUE if the data pointed to by ValueName is successfully converted into ASCII and copied into the buffer. This routine returns FALSE in the event of an error.

Remarks

If StorPortRegistryRead returns FALSE with a nonzero value in the BufferLength parameter, the buffer that was passed was too small and the BufferLength parameter reflects the correct buffer size that should be used. If the routine returns FALSE with the BufferLength parameter set to zero, another error has occurred.

The buffer used in this routine is allocated by calling StorPortAllocateRegistryBuffer and freed by calling StorPortFreeRegistryBuffer.

Requirements

Requirement	Value
Target Platform	Universal
Header	storport.h (include Storport.h)
Library	Storport.lib
IRQL	PASSIVE_LEVEL
DDI compliance rules	StorPortIrql(storport)