NdisOpenFile

NdisOpenFile

VOID
NdisOpenFile(
OUT PNDIS_STATUS Status,
OUT PNDIS_HANDLE FileHandle,
OUT PUINT FileLength,
IN PNDIS_STRING FileName,
IN NDIS_PHYSICAL_ADDRESS HighestAcceptableAddress
);

NdisOpenFile returns a handle for an opened file.

Parameters

Status

Points to a caller-supplied variable in which this function returns the status of the open file operation, which can be one of the following:

NDIS_STATUS_SUCCESS

The handle at FileHandle is valid for a subsequent call to NdisMapFile.

NDIS_STATUS_FILE_NOT_FOUND

The given string at FileName did not specify a name found in the system object namespace.

NDIS_STATUS_RESOURCES

NDIS could not allocate the resources it needed to open the file and allocate a buffer for the file contents.

NDIS_STATUS_ERROR_READING_FILE

The specified file's data could not be read into system memory for subsequent access by the caller.

FileHandle

Points to a caller-supplied variable in which this function returns the handle of the opened file if the call succeeds.

FileLength

Points to a caller-supplied variable in which this function writes the number of bytes of data in the opened file if the call succeeds.

FileName

Points to a buffered, caller-initialized counted string, in the system-default character set, naming the file to be opened. For Windows NT drivers, this string contains Unicode characters.

HighestAcceptableAddress

Specifies the highest physical address in which the file data can be stored, or specifies -1 if the driver places no restrictions.

Comments

NdisOpenFile opens a disk file, typically a file the driver will later download to program an intelligent NIC. NdisOpenFile also allocates storage to hold file contents for the driver's subsequent call to NdisMapFile.

A NIC driver should call NdisOpenFile only from MiniportInitialize.

When NdisOpenFile returns, the NIC driver can access file data by calling NdisMapFile. It can call NdisUnmapFile to page out the file so it does not consume resources unnecessarily while the driver is not accessing the file data. When finished using the file, MiniportInitialize must call NdisCloseFile.

Callers of NdisOpenFile run at IRQL PASSIVE_LEVEL.