#include <Uefi.h>
#include <Guid/FileInfo.h>
#include <Guid/FileSystemInfo.h>
#include <Guid/FileSystemVolumeLabelInfo.h>
#include <Library/BaseLib.h>
#include <Library/BaseMemoryLib.h>
#include <Library/DebugLib.h>
#include <Library/MemoryAllocationLib.h>
#include <Library/SemihostLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include <Library/UefiLib.h>
#include <Protocol/DevicePath.h>
#include <Protocol/SimpleFileSystem.h>
#include "SemihostFs.h"

Data Structures
struct	SEMIHOST_DEVICE_PATH

struct	SEMIHOST_FCB

Macros
#define	DEFAULT_SEMIHOST_FS_LABEL L"SemihostFs"

#define	SEMIHOST_FCB_SIGNATURE SIGNATURE_32( 'S', 'H', 'F', 'C' )

#define	SEMIHOST_FCB_FROM_THIS(a) CR(a, SEMIHOST_FCB, File, SEMIHOST_FCB_SIGNATURE)

#define	SEMIHOST_FCB_FROM_LINK(a) CR(a, SEMIHOST_FCB, Link, SEMIHOST_FCB_SIGNATURE);

Functions
SEMIHOST_FCB *	AllocateFCB (VOID)

VOID	FreeFCB (IN SEMIHOST_FCB *Fcb)

EFI_STATUS	VolumeOpen (IN EFI_SIMPLE_FILE_SYSTEM_PROTOCOL This, OUT EFI_FILE *Root)

EFI_STATUS	FileOpen (IN EFI_FILE This, OUT EFI_FILE NewHandle, IN CHAR16 FileName, IN UINT64 OpenMode, IN UINT64 Attributes)

STATIC EFI_STATUS	TruncateFile (IN CHAR8 *FileName, IN UINTN Size)

EFI_STATUS	FileClose (IN EFI_FILE *This)

EFI_STATUS	FileDelete (IN EFI_FILE *This)

EFI_STATUS	FileRead (IN EFI_FILE This, IN OUT UINTN BufferSize, OUT VOID *Buffer)

STATIC EFI_STATUS	ExtendFile (IN SEMIHOST_FCB *Fcb, IN UINTN Size)

EFI_STATUS	FileWrite (IN EFI_FILE This, IN OUT UINTN BufferSize, IN VOID *Buffer)

EFI_STATUS	FileGetPosition (IN EFI_FILE This, OUT UINT64 Position)

EFI_STATUS	FileSetPosition (IN EFI_FILE *This, IN UINT64 Position)

STATIC EFI_STATUS	GetFileInfo (IN SEMIHOST_FCB Fcb, IN OUT UINTN BufferSize, OUT VOID *Buffer)

STATIC EFI_STATUS	GetFilesystemInfo (IN SEMIHOST_FCB Fcb, IN OUT UINTN BufferSize, OUT VOID *Buffer)

EFI_STATUS	FileGetInfo (IN EFI_FILE This, IN EFI_GUID InformationType, IN OUT UINTN BufferSize, OUT VOID Buffer)

STATIC EFI_STATUS	SetFileInfo (IN SEMIHOST_FCB Fcb, IN EFI_FILE_INFO Info)

EFI_STATUS	FileSetInfo (IN EFI_FILE This, IN EFI_GUID InformationType, IN UINTN BufferSize, IN VOID *Buffer)

EFI_STATUS	FileFlush (IN EFI_FILE *File)

EFI_STATUS	SemihostFsEntryPoint (IN EFI_HANDLE ImageHandle, IN EFI_SYSTEM_TABLE *SystemTable)

Variables
STATIC CHAR16 *	mSemihostFsLabel

EFI_SIMPLE_FILE_SYSTEM_PROTOCOL	gSemihostFs

EFI_FILE	gSemihostFsFile

SEMIHOST_DEVICE_PATH	gDevicePath

EFI_HANDLE	gInstallHandle = NULL

LIST_ENTRY	gFileList = INITIALIZE_LIST_HEAD_VARIABLE (gFileList)

Detailed Description

Support a Semi Host file system over a debuggers JTAG

SPDX-License-Identifier: BSD-2-Clause-Patent

Definition in file SemihostFs.c.

Macro Definition Documentation

◆ DEFAULT_SEMIHOST_FS_LABEL

#define DEFAULT_SEMIHOST_FS_LABEL L"SemihostFs"

Definition at line 30 of file SemihostFs.c.

◆ SEMIHOST_FCB_FROM_LINK

#define SEMIHOST_FCB_FROM_LINK ( a ) CR(a, SEMIHOST_FCB, Link, SEMIHOST_FCB_SIGNATURE);

Definition at line 85 of file SemihostFs.c.

◆ SEMIHOST_FCB_FROM_THIS

#define SEMIHOST_FCB_FROM_THIS ( a ) CR(a, SEMIHOST_FCB, File, SEMIHOST_FCB_SIGNATURE)

Definition at line 84 of file SemihostFs.c.

◆ SEMIHOST_FCB_SIGNATURE

#define SEMIHOST_FCB_SIGNATURE SIGNATURE_32( 'S', 'H', 'F', 'C' )

Definition at line 83 of file SemihostFs.c.

Function Documentation

◆ AllocateFCB()

SEMIHOST_FCB * AllocateFCB ( VOID )

Definition at line 91 of file SemihostFs.c.

◆ ExtendFile()

STATIC EFI_STATUS ExtendFile	(	IN SEMIHOST_FCB *	Fcb,
		IN UINTN	Size
	)

Worker function that extends the size of an open file.

The extension is filled with zeros.

Parameters

[in]	Fcb	Internal description of the opened file
[in]	Size	The number of bytes, the file has to be extended.

Return values

EFI_SUCCESS	The file was extended.
EFI_DEVICE_ERROR	The last issued semi-hosting operation failed.

Definition at line 560 of file SemihostFs.c.

◆ FileClose()

EFI_STATUS FileClose ( IN EFI_FILE * This )

Close a specified file handle.

Parameters

[in] This A pointer to the EFI_FILE_PROTOCOL instance that is the file handle to close.

Return values

EFI_SUCCESS	The file was closed.
EFI_INVALID_PARAMETER	The parameter "This" is NULL.

Definition at line 407 of file SemihostFs.c.

◆ FileDelete()

EFI_STATUS FileDelete ( IN EFI_FILE * This )

Close and delete a file.

Parameters

[in] This A pointer to the EFI_FILE_PROTOCOL instance that is the file handle to delete.

Return values

EFI_SUCCESS	The file was closed and deleted.
EFI_WARN_DELETE_FAILURE	The handle was closed, but the file was not deleted.
EFI_INVALID_PARAMETER	The parameter "This" is NULL.

Definition at line 450 of file SemihostFs.c.

◆ FileFlush()

EFI_STATUS FileFlush ( IN EFI_FILE * File )

Definition at line 1181 of file SemihostFs.c.

◆ FileGetInfo()

EFI_STATUS FileGetInfo	(	IN EFI_FILE *	This,
		IN EFI_GUID *	InformationType,
		IN OUT UINTN *	BufferSize,
		OUT VOID *	Buffer
	)

Return information about a file or a file system.

Parameters

[in]	This	A pointer to the EFI_FILE_PROTOCOL instance that is the file handle the requested information is for.
[in]	InformationType	The type identifier for the information being requested : EFI_FILE_INFO_ID or EFI_FILE_SYSTEM_INFO_ID or EFI_FILE_SYSTEM_VOLUME_LABEL_ID
[in,out]	BufferSize	The size, in bytes, of Buffer.
[out]	Buffer	A pointer to the data buffer to return. The type of the data inside the buffer is indicated by InformationType.

Return values

EFI_SUCCESS	The information was returned.
EFI_UNSUPPORTED	The InformationType is not known.
EFI_BUFFER_TOO_SMALL	The BufferSize is too small to return the information. BufferSize has been updated with the size needed to complete the request.
EFI_INVALID_PARAMETER	The parameter "This" or "InformationType" or "BufferSize" is NULL or "Buffer" is NULL and "*Buffersize" is greater than 0.

Definition at line 890 of file SemihostFs.c.

◆ FileGetPosition()

EFI_STATUS FileGetPosition	(	IN EFI_FILE *	This,
		OUT UINT64 *	Position
	)

Return a file's current position.

Parameters

[in]	This	A pointer to the EFI_FILE_PROTOCOL instance that is the file handle to get the current position on.
[out]	Position	The address to return the file's current position value.

Return values

EFI_SUCCESS	The position was returned.
EFI_INVALID_PARAMETER	The parameter "This" or "Position" is NULL.

Definition at line 682 of file SemihostFs.c.

◆ FileOpen()

EFI_STATUS FileOpen	(	IN EFI_FILE *	This,
		OUT EFI_FILE **	NewHandle,
		IN CHAR16 *	FileName,
		IN UINT64	OpenMode,
		IN UINT64	Attributes
	)

Open a file on the host system by means of the semihosting interface.

Parameters

[in]	This	A pointer to the EFI_FILE_PROTOCOL instance that is the file handle to source location.
[out]	NewHandle	A pointer to the location to return the opened handle for the new file.
[in]	FileName	The Null-terminated string of the name of the file to be opened.
[in]	OpenMode	The mode to open the file : Read or Read/Write or Read/Write/Create
[in]	Attributes	Only valid for EFI_FILE_MODE_CREATE, in which case these are the attribute bits for the newly created file. The mnemonics of the attribute bits are : EFI_FILE_READ_ONLY, EFI_FILE_HIDDEN, EFI_FILE_SYSTEM, EFI_FILE_RESERVED, EFI_FILE_DIRECTORY and EFI_FILE_ARCHIVE.

Return values

EFI_SUCCESS	The file was open.
EFI_NOT_FOUND	The specified file could not be found.
EFI_DEVICE_ERROR	The last issued semi-hosting operation failed.
EFI_WRITE_PROTECTED	Attempt to create a directory. This is not possible with the semi-hosting interface.
EFI_OUT_OF_RESOURCES	Not enough resources were available to open the file.
EFI_INVALID_PARAMETER	At least one of the parameters is invalid.

Definition at line 174 of file SemihostFs.c.

◆ FileRead()

EFI_STATUS FileRead	(	IN EFI_FILE *	This,
		IN OUT UINTN *	BufferSize,
		OUT VOID *	Buffer
	)

Read data from an open file.

Parameters

[in]	This	A pointer to the EFI_FILE_PROTOCOL instance that is the file handle to read data from.
[in,out]	BufferSize	On input, the size of the Buffer. On output, the amount of data returned in Buffer. In both cases, the size is measured in bytes.
[out]	Buffer	The buffer into which the data is read.

Return values

EFI_SUCCESS	The data was read.
EFI_DEVICE_ERROR	On entry, the current file position is beyond the end of the file, or the semi-hosting interface reported an error while performing the read operation.
EFI_INVALID_PARAMETER	At least one of the three input pointers is NULL.

Definition at line 507 of file SemihostFs.c.

◆ FileSetInfo()

EFI_STATUS FileSetInfo	(	IN EFI_FILE *	This,
		IN EFI_GUID *	InformationType,
		IN UINTN	BufferSize,
		IN VOID *	Buffer
	)

Set information about a file or a file system.

Parameters

[in]	This	A pointer to the EFI_FILE_PROTOCOL instance that is the file handle the information is for.
[in]	InformationType	The type identifier for the information being set : EFI_FILE_INFO_ID or EFI_FILE_SYSTEM_INFO_ID or EFI_FILE_SYSTEM_VOLUME_LABEL_ID
[in]	BufferSize	The size, in bytes, of Buffer.
[in]	Buffer	A pointer to the data buffer to write. The type of the data inside the buffer is indicated by InformationType.

Return values

EFI_SUCCESS	The information was set.
EFI_UNSUPPORTED	The InformationType is not known.
EFI_DEVICE_ERROR	The last issued semi-hosting operation failed.
EFI_ACCESS_DENIED	An attempt is being made to change the EFI_FILE_DIRECTORY Attribute.
EFI_ACCESS_DENIED	InformationType is EFI_FILE_INFO_ID and the file is a read-only file or has been opened in read-only mode and an attempt is being made to modify a field other than Attribute.
EFI_ACCESS_DENIED	An attempt is made to change the name of a file to a file that is already present.
EFI_WRITE_PROTECTED	An attempt is being made to modify a read-only attribute.
EFI_BAD_BUFFER_SIZE	The size of the buffer is lower than that indicated by the data inside the buffer.
EFI_OUT_OF_RESOURCES	An allocation needed to process the request failed.
EFI_INVALID_PARAMETER	At least one of the parameters is invalid.

Definition at line 1118 of file SemihostFs.c.

◆ FileSetPosition()

EFI_STATUS FileSetPosition	(	IN EFI_FILE *	This,
		IN UINT64	Position
	)

Set a file's current position.

Parameters

[in]	This	A pointer to the EFI_FILE_PROTOCOL instance that is the file handle to set the requested position on.
[in]	Position	The byte position from the start of the file to set.

Return values

EFI_SUCCESS	The position was set.
EFI_DEVICE_ERROR	The semi-hosting positioning operation failed.
EFI_UNSUPPORTED	The seek request for nonzero is not valid on open directories.
EFI_INVALID_PARAMETER	The parameter "This" is NULL.

Definition at line 715 of file SemihostFs.c.

◆ FileWrite()

EFI_STATUS FileWrite	(	IN EFI_FILE *	This,
		IN OUT UINTN *	BufferSize,
		IN VOID *	Buffer
	)

Write data to an open file.

Parameters

[in]	This	A pointer to the EFI_FILE_PROTOCOL instance that is the file handle to write data to.
[in,out]	BufferSize	On input, the size of the Buffer. On output, the size of the data actually written. In both cases, the size is measured in bytes.
[in]	Buffer	The buffer of data to write.

Return values

EFI_SUCCESS	The data was written.
EFI_ACCESS_DENIED	Attempt to write into a read only file or in a file opened in read only mode.
EFI_DEVICE_ERROR	The last issued semi-hosting operation failed.
EFI_INVALID_PARAMETER	At least one of the three input pointers is NULL.

Definition at line 610 of file SemihostFs.c.

◆ FreeFCB()

VOID FreeFCB ( IN SEMIHOST_FCB * Fcb )

Definition at line 107 of file SemihostFs.c.

◆ GetFileInfo()

STATIC EFI_STATUS GetFileInfo	(	IN SEMIHOST_FCB *	Fcb,
		IN OUT UINTN *	BufferSize,
		OUT VOID *	Buffer
	)

Return information about a file.

Parameters

[in]	Fcb	A pointer to the description of an open file.
[in,out]	BufferSize	The size, in bytes, of Buffer.
[out]	Buffer	A pointer to the data buffer to return. Not NULL if "*BufferSize" is greater than 0.

Return values

EFI_SUCCESS	The information was returned.
EFI_BUFFER_TOO_SMALL	The BufferSize is too small to return the information. BufferSize has been updated with the size needed to complete the request.

Definition at line 769 of file SemihostFs.c.

◆ GetFilesystemInfo()

STATIC EFI_STATUS GetFilesystemInfo	(	IN SEMIHOST_FCB *	Fcb,
		IN OUT UINTN *	BufferSize,
		OUT VOID *	Buffer
	)

Return information about a file system.

Parameters

[in]	Fcb	A pointer to the description of an open file which belongs to the file system, the information is requested for.
[in,out]	BufferSize	The size, in bytes, of Buffer.
[out]	Buffer	A pointer to the data buffer to return. Not NULL if "*BufferSize" is greater than 0.

Return values

EFI_SUCCESS	The information was returned.
EFI_BUFFER_TOO_SMALL	The BufferSize is too small to return the information. BufferSize has been updated with the size needed to complete the request.

Definition at line 832 of file SemihostFs.c.

◆ SemihostFsEntryPoint()

EFI_STATUS SemihostFsEntryPoint	(	IN EFI_HANDLE	ImageHandle,
		IN EFI_SYSTEM_TABLE *	SystemTable
	)

Definition at line 1203 of file SemihostFs.c.

◆ SetFileInfo()

STATIC EFI_STATUS SetFileInfo	(	IN SEMIHOST_FCB *	Fcb,
		IN EFI_FILE_INFO *	Info
	)

Set information about a file.

Parameters

[in]	Fcb	A pointer to the description of the open file.
[in]	Info	A pointer to the file information to write.

Return values

EFI_SUCCESS	The information was set.
EFI_ACCESS_DENIED	An attempt is made to change the name of a file to a file that is already present.
EFI_ACCESS_DENIED	An attempt is being made to change the EFI_FILE_DIRECTORY Attribute.
EFI_ACCESS_DENIED	The file is a read-only file or has been opened in read-only mode and an attempt is being made to modify a field other than Attribute.
EFI_WRITE_PROTECTED	An attempt is being made to modify a read-only attribute.
EFI_DEVICE_ERROR	The last issued semi-hosting operation failed.
EFI_OUT_OF_RESOURCES	A allocation needed to process the request failed.

Definition at line 956 of file SemihostFs.c.

◆ TruncateFile()

STATIC EFI_STATUS TruncateFile	(	IN CHAR8 *	FileName,
		IN UINTN	Size
	)

Worker function that truncate a file specified by its name to a given size.

Parameters

[in]	FileName	The Null-terminated string of the name of the file to be opened.
[in]	Size	The target size for the file.

Return values

EFI_SUCCESS	The file was truncated.
EFI_DEVICE_ERROR	The last issued semi-hosting operation failed.

Definition at line 314 of file SemihostFs.c.

◆ VolumeOpen()

EFI_STATUS VolumeOpen	(	IN EFI_SIMPLE_FILE_SYSTEM_PROTOCOL *	This,
		OUT EFI_FILE **	Root
	)

Definition at line 121 of file SemihostFs.c.

Variable Documentation

◆ gDevicePath

SEMIHOST_DEVICE_PATH gDevicePath

Initial value:

= {
  {
    { HARDWARE_DEVICE_PATH, HW_VENDOR_DP,                   { sizeof (VENDOR_DEVICE_PATH),       0 }
    },
    EFI_CALLER_ID_GUID
  },
  { END_DEVICE_PATH_TYPE, END_ENTIRE_DEVICE_PATH_SUBTYPE, { sizeof (EFI_DEVICE_PATH_PROTOCOL), 0 }
  }
}

Definition at line 61 of file SemihostFs.c.

◆ gFileList

LIST_ENTRY gFileList = INITIALIZE_LIST_HEAD_VARIABLE (gFileList)

Definition at line 88 of file SemihostFs.c.

◆ gInstallHandle

EFI_HANDLE gInstallHandle = NULL

Definition at line 87 of file SemihostFs.c.

◆ gSemihostFs

EFI_SIMPLE_FILE_SYSTEM_PROTOCOL gSemihostFs

Initial value:

= {
  EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_REVISION,
  VolumeOpen
}

Definition at line 34 of file SemihostFs.c.

◆ gSemihostFsFile

EFI_FILE gSemihostFsFile

Initial value:

= {
  EFI_FILE_PROTOCOL_REVISION,
  FileOpen,
  FileClose,
  FileDelete,
  FileRead,
  FileWrite,
  FileGetPosition,
  FileSetPosition,
  FileGetInfo,
  FileSetInfo,
  FileFlush
}

Definition at line 39 of file SemihostFs.c.

◆ mSemihostFsLabel

STATIC CHAR16* mSemihostFsLabel

Definition at line 32 of file SemihostFs.c.

Data Structures

Macros

Functions

Variables

Detailed Description

Macro Definition Documentation

◆ DEFAULT_SEMIHOST_FS_LABEL

◆ SEMIHOST_FCB_FROM_LINK

◆ SEMIHOST_FCB_FROM_THIS

◆ SEMIHOST_FCB_SIGNATURE

Function Documentation

◆ AllocateFCB()

◆ ExtendFile()

◆ FileClose()

◆ FileDelete()

◆ FileFlush()

◆ FileGetInfo()

◆ FileGetPosition()

◆ FileOpen()

◆ FileRead()

◆ FileSetInfo()

◆ FileSetPosition()

◆ FileWrite()

◆ FreeFCB()

◆ GetFileInfo()

◆ GetFilesystemInfo()

◆ SemihostFsEntryPoint()

◆ SetFileInfo()

◆ TruncateFile()

◆ VolumeOpen()

Variable Documentation

◆ gDevicePath

◆ gFileList

◆ gInstallHandle

◆ gSemihostFs

◆ gSemihostFsFile

◆ mSemihostFsLabel