/** @file
Basic command line parser for EBL (Embedded Boot Loader)
Copyright (c) 2007, Intel Corporation. All rights reserved.<BR>
Portions copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
(C) Copyright 2015 Hewlett Packard Enterprise Development LP<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
**/
#include "Ebl.h"
// Globals for command history processing
INTN mCmdHistoryEnd = -1;
INTN mCmdHistoryStart = -1;
INTN mCmdHistoryCurrent = -1;
CHAR8 mCmdHistory[MAX_CMD_HISTORY][MAX_CMD_LINE];
CHAR8 *mCmdBlank = "";
// Globals to remember current screen geometry
UINTN gScreenColumns;
UINTN gScreenRows;
// Global to turn on/off breaking commands with prompts before they scroll the screen
BOOLEAN gPageBreak = TRUE;
VOID
RingBufferIncrement (
IN INTN *Value
)
{
*Value = *Value + 1;
if (*Value >= MAX_CMD_HISTORY) {
*Value = 0;
}
}
VOID
RingBufferDecrement (
IN INTN *Value
)
{
*Value = *Value - 1;
if (*Value < 0) {
*Value = MAX_CMD_HISTORY - 1;
}
}
/**
Save this command in the circular history buffer. Older commands are
overwritten with newer commands.
@param Cmd Command line to archive the history of.
@return None
**/
VOID
SetCmdHistory (
IN CHAR8 *Cmd
)
{
// Don't bother adding empty commands to the list
if (AsciiStrLen(Cmd) != 0) {
// First entry
if (mCmdHistoryStart == -1) {
mCmdHistoryStart = 0;
mCmdHistoryEnd = 0;
} else {
// Record the new command at the next index
RingBufferIncrement(&mCmdHistoryStart);
// If the next index runs into the end index, shuffle end back by one
if (mCmdHistoryStart == mCmdHistoryEnd) {
RingBufferIncrement(&mCmdHistoryEnd);
}
}
// Copy the new command line into the ring buffer
AsciiStrnCpyS (&mCmdHistory[mCmdHistoryStart][0], MAX_CMD_LINE, Cmd, MAX_CMD_LINE);
}
// Reset the command history for the next up arrow press
mCmdHistoryCurrent = mCmdHistoryStart;
}
/**
Retreave data from the Command History buffer. Direction maps into up arrow
an down arrow on the command line
@param Direction Command forward or back
@return The Command history based on the Direction
**/
CHAR8 *
GetCmdHistory (
IN UINT16 Direction
)
{
CHAR8 *HistoricalCommand = NULL;
// No history yet?
if (mCmdHistoryCurrent == -1) {
HistoricalCommand = mCmdBlank;
goto Exit;
}
if (Direction == SCAN_UP) {
HistoricalCommand = &mCmdHistory[mCmdHistoryCurrent][0];
// if we just echoed the last command, hang out there, don't wrap around
if (mCmdHistoryCurrent == mCmdHistoryEnd) {
goto Exit;
}
// otherwise, back up by one
RingBufferDecrement(&mCmdHistoryCurrent);
} else if (Direction == SCAN_DOWN) {
// if we last echoed the start command, put a blank prompt out
if (mCmdHistoryCurrent == mCmdHistoryStart) {
HistoricalCommand = mCmdBlank;
goto Exit;
}
// otherwise increment the current pointer and return that command
RingBufferIncrement(&mCmdHistoryCurrent);
RingBufferIncrement(&mCmdHistoryCurrent);
HistoricalCommand = &mCmdHistory[mCmdHistoryCurrent][0];
RingBufferDecrement(&mCmdHistoryCurrent);
}
Exit:
return HistoricalCommand;
}
/**
Parse the CmdLine and break it up into Argc (arg count) and Argv (array of
pointers to each argument). The Cmd buffer is altered and separators are
converted to string terminators. This allows Argv to point into CmdLine.
A CmdLine can support multiple commands. The next command in the command line
is returned if it exists.
@param CmdLine String to parse for a set of commands
@param Argc Returns the number of arguments in the CmdLine current command
@param Argv Argc pointers to each string in CmdLine
@return Next Command in the command line or NULL if non exists
**/
CHAR8 *
ParseArguments (
IN CHAR8 *CmdLine,
OUT UINTN *Argc,
OUT CHAR8 **Argv
)
{
UINTN Arg;
CHAR8 *Char;
BOOLEAN LookingForArg;
BOOLEAN InQuote;
*Argc = 0;
if (AsciiStrLen (CmdLine) == 0) {
return NULL;
}
// Walk a single command line. A CMD_SEPARATOR allows multiple commands on a single line
InQuote = FALSE;
LookingForArg = TRUE;
for (Char = CmdLine, Arg = 0; *Char != '\0'; Char++) {
if (!InQuote && *Char == CMD_SEPARATOR) {
break;
}
// Perform any text conversion here
if (*Char == '\t') {
// TAB to space
*Char = ' ';
}
if (LookingForArg) {
// Look for the beginning of an Argv[] entry
if (*Char == '"') {
Argv[Arg++] = ++Char;
LookingForArg = FALSE;
InQuote = TRUE;
} else if (*Char != ' ') {
Argv[Arg++] = Char;
LookingForArg = FALSE;
}
} else {
// Looking for the terminator of an Argv[] entry
if (!InQuote && (*Char == ' ')) {
*Char = '\0';
LookingForArg = TRUE;
} else if (!InQuote && (*Char == '"') && (*(Char-1) != '\\')) {
InQuote = TRUE;
} else if (InQuote && (*Char == '"') && (*(Char-1) != '\\')) {
*Char = '\0';
InQuote = FALSE;
}
}
}
*Argc = Arg;
if (*Char == CMD_SEPARATOR) {
// Replace the command delimiter with null and return pointer to next command line
*Char = '\0';
return ++Char;
}
return NULL;
}
/**
Return a keypress or optionally timeout if a timeout value was passed in.
An optional callback function is called every second when waiting for a
timeout.
@param Key EFI Key information returned
@param TimeoutInSec Number of seconds to wait to timeout
@param CallBack Callback called every second during the timeout wait
@return EFI_SUCCESS Key was returned
@return EFI_TIMEOUT If the TimoutInSec expired
**/
EFI_STATUS
EFIAPI
EblGetCharKey (
IN OUT EFI_INPUT_KEY *Key,
IN UINTN TimeoutInSec,
IN EBL_GET_CHAR_CALL_BACK CallBack OPTIONAL
)
{
EFI_STATUS Status;
UINTN WaitCount;
UINTN WaitIndex;
EFI_EVENT WaitList[2];
WaitCount = 1;
WaitList[0] = gST->ConIn->WaitForKey;
if (TimeoutInSec != 0) {
// Create a time event for 1 sec duration if we have a timeout
gBS->CreateEvent (EVT_TIMER, 0, NULL, NULL, &WaitList[1]);
gBS->SetTimer (WaitList[1], TimerPeriodic, EFI_SET_TIMER_TO_SECOND);
WaitCount++;
}
for (;;) {
Status = gBS->WaitForEvent (WaitCount, WaitList, &WaitIndex);
ASSERT_EFI_ERROR (Status);
switch (WaitIndex) {
case 0:
// Key event signaled
Status = gST->ConIn->ReadKeyStroke (gST->ConIn, Key);
if (!EFI_ERROR (Status)) {
if (WaitCount == 2) {
gBS->CloseEvent (WaitList[1]);
}
return EFI_SUCCESS;
}
break;
case 1:
// Periodic 1 sec timer signaled
TimeoutInSec--;
if (CallBack != NULL) {
// Call the users callback function if registered
CallBack (TimeoutInSec);
}
if (TimeoutInSec == 0) {
gBS->CloseEvent (WaitList[1]);
return EFI_TIMEOUT;
}
break;
default:
ASSERT (FALSE);
}
}
}
/**
This routine is used prevent command output data from scrolling off the end
of the screen. The global gPageBreak is used to turn on or off this feature.
If the CurrentRow is near the end of the screen pause and print out a prompt
If the use hits Q to quit return TRUE else for any other key return FALSE.
PrefixNewline is used to figure out if a newline is needed before the prompt
string. This depends on the last print done before calling this function.
CurrentRow is updated by one on a call or set back to zero if a prompt is
needed.
@param CurrentRow Used to figure out if its the end of the page and updated
@param PrefixNewline Did previous print issue a newline
@return TRUE if Q was hit to quit, FALSE in all other cases.
**/
BOOLEAN
EFIAPI
EblAnyKeyToContinueQtoQuit (
IN UINTN *CurrentRow,
IN BOOLEAN PrefixNewline
)
{
EFI_INPUT_KEY InputKey;
if (!gPageBreak) {
// global disable for this feature
return FALSE;
}
if (*CurrentRow >= (gScreenRows - 2)) {
if (PrefixNewline) {
AsciiPrint ("\n");
}
AsciiPrint ("Any key to continue (Q to quit): ");
EblGetCharKey (&InputKey, 0, NULL);
AsciiPrint ("\n");
// Time to promt to stop the screen. We have to leave space for the prompt string
*CurrentRow = 0;
if (InputKey.UnicodeChar == 'Q' || InputKey.UnicodeChar == 'q') {
return TRUE;
}
} else {
*CurrentRow += 1;
}
return FALSE;
}
/**
Set the text color of the EFI Console. If a zero is passed in reset to
default text/background color.
@param Attribute For text and background color
**/
VOID
EblSetTextColor (
UINTN Attribute
)
{
if (Attribute == 0) {
// Set the text color back to default
Attribute = (UINTN)PcdGet32 (PcdEmbeddedDefaultTextColor);
}
gST->ConOut->SetAttribute (gST->ConOut, Attribute);
}
/**
Collect the keyboard input for a cmd line. Carriage Return, New Line, or ESC
terminates the command line. You can edit the command line via left arrow,
delete and backspace and they all back up and erase the command line.
No edit of command line is possible without deletion at this time!
The up arrow and down arrow fill Cmd with information from the history
buffer.
@param Cmd Command line to return
@param CmdMaxSize Maximum size of Cmd
@return The Status of EblGetCharKey()
**/
EFI_STATUS
GetCmd (
IN OUT CHAR8 *Cmd,
IN UINTN CmdMaxSize
)
{
EFI_STATUS Status;
UINTN Index;
UINTN Index2;
CHAR8 Char;
CHAR8 *History;
EFI_INPUT_KEY Key;
for (Index = 0; Index < CmdMaxSize - 1;) {
Status = EblGetCharKey (&Key, 0, NULL);
if (EFI_ERROR (Status)) {
Cmd[Index] = '\0';
AsciiPrint ("\n");
return Status;
}
Char = (CHAR8)Key.UnicodeChar;
if ((Char == '\n') || (Char == '\r') || (Char == 0x7f)) {
Cmd[Index] = '\0';
if (FixedPcdGetBool(PcdEmbeddedShellCharacterEcho) == TRUE) {
AsciiPrint ("\n\r");
}
return EFI_SUCCESS;
} else if ((Char == '\b') || (Key.ScanCode == SCAN_LEFT) || (Key.ScanCode == SCAN_DELETE)){
if (Index != 0) {
Index--;
//
// Update the display
//
AsciiPrint ("\b \b");
}
} else if ((Key.ScanCode == SCAN_UP) || Key.ScanCode == SCAN_DOWN) {
History = GetCmdHistory (Key.ScanCode);
//
// Clear display line
//
for (Index2 = 0; Index2 < Index; Index2++) {
AsciiPrint ("\b \b");
}
AsciiPrint (History);
Index = AsciiStrLen (History);
AsciiStrnCpyS (Cmd, CmdMaxSize, History, CmdMaxSize);
} else {
Cmd[Index++] = Char;
if (FixedPcdGetBool(PcdEmbeddedShellCharacterEcho) == TRUE) {
AsciiPrint ("%c", Char);
}
}
}
return EFI_SUCCESS;
}
/**
Print the boot up banner for the EBL.
**/
VOID
EblPrintStartupBanner (
VOID
)
{
AsciiPrint ("Embedded Boot Loader (");
EblSetTextColor (EFI_YELLOW);
AsciiPrint ("EBL");
EblSetTextColor (0);
AsciiPrint (") prototype. Built at %a on %a\n",__TIME__, __DATE__);
AsciiPrint ("THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN 'AS IS' BASIS,\nWITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\n");
AsciiPrint ("Please send feedback to edk2-devel@lists.sourceforge.net\n");
}
/**
Send null requests to all removable media block IO devices so the a media add/remove/change
can be detected in real before we execute a command.
This is mainly due to the fact that the FAT driver does not do this today so you can get stale
dir commands after an SD Card has been removed.
**/
VOID
EblProbeRemovableMedia (
VOID
)
{
UINTN Index;
UINTN Max;
EFI_OPEN_FILE *File;
//
// Probe for media insertion/removal in removable media devices
//
Max = EfiGetDeviceCounts (EfiOpenBlockIo);
if (Max != 0) {
for (Index = 0; Index < Max; Index++) {
File = EfiDeviceOpenByType (EfiOpenBlockIo, Index);
if (File != NULL) {
if (File->FsBlockIoMedia->RemovableMedia) {
// Probe to see if media is present (or not) or media changed
// this causes the ReinstallProtocolInterface() to fire in the
// block io driver to update the system about media change events
File->FsBlockIo->ReadBlocks (File->FsBlockIo, File->FsBlockIo->Media->MediaId, (EFI_LBA)0, 0, NULL);
}
EfiClose (File);
}
}
}
}
/**
Print the prompt for the EBL.
**/
VOID
EblPrompt (
VOID
)
{
EblSetTextColor (EFI_YELLOW);
AsciiPrint ("%a %a",(CHAR8 *)PcdGetPtr (PcdEmbeddedPrompt), EfiGetCwd ());
EblSetTextColor (0);
AsciiPrint ("%a", ">");
}
/**
Parse a command line and execute the commands. The ; separator allows
multiple commands for each command line. Stop processing if one of the
commands returns an error.
@param CmdLine Command Line to process.
@param MaxCmdLineSize MaxSize of the Command line
@return EFI status of the Command
**/
EFI_STATUS
ProcessCmdLine (
IN CHAR8 *CmdLine,
IN UINTN MaxCmdLineSize
)
{
EFI_STATUS Status;
EBL_COMMAND_TABLE *Cmd;
CHAR8 *Ptr;
UINTN Argc;
CHAR8 *Argv[MAX_ARGS];
// Parse the command line. The loop processes commands separated by ;
for (Ptr = CmdLine, Status = EFI_SUCCESS; Ptr != NULL;) {
Ptr = ParseArguments (Ptr, &Argc, Argv);
if (Argc != 0) {
Cmd = EblGetCommand (Argv[0]);
if (Cmd != NULL) {
// Execute the Command!
Status = Cmd->Command (Argc, Argv);
if (Status == EFI_ABORTED) {
// exit command so lets exit
break;
} else if (Status == EFI_TIMEOUT) {
// pause command got input so don't process any more cmd on this cmd line
break;
} else if (EFI_ERROR (Status)) {
AsciiPrint ("%a returned %r error\n", Cmd->Name, Status);
// if any command fails stop processing CmdLine
break;
}
} else {
AsciiPrint ("The command '%a' is not supported.\n", Argv[0]);
}
}
}
return Status;
}
/**
Embedded Boot Loader (EBL) - A simple EFI command line application for embedded
devices. PcdEmbeddedAutomaticBootCommand is a complied in command line that
gets executed automatically. The ; separator allows multiple commands
for each command line.
@param ImageHandle EFI ImageHandle for this application.
@param SystemTable EFI system table
@return EFI status of the application
**/
EFI_STATUS
EFIAPI
EdkBootLoaderEntry (
IN EFI_HANDLE ImageHandle,
IN EFI_SYSTEM_TABLE *SystemTable
)
{
EFI_STATUS Status;
CHAR8 CmdLine[MAX_CMD_LINE];
CHAR16 *CommandLineVariable = NULL;
CHAR16 *CommandLineVariableName = L"default-cmdline";
UINTN CommandLineVariableSize = 0;
EFI_GUID VendorGuid;
// Initialize tables of commands
EblInitializeCmdTable ();
EblInitializeDeviceCmd ();
EblInitializemdHwDebugCmds ();
EblInitializemdHwIoDebugCmds ();
EblInitializeDirCmd ();
EblInitializeHobCmd ();
EblInitializeScriptCmd ();
EblInitializeExternalCmd ();
EblInitializeNetworkCmd();
EblInitializeVariableCmds ();
if (gST->ConOut == NULL) {
DEBUG((EFI_D_ERROR,"Error: No Console Output\n"));
return EFI_NOT_READY;
}
// Disable the 5 minute EFI watchdog time so we don't get automatically reset
gBS->SetWatchdogTimer (0, 0, 0, NULL);
if (FeaturePcdGet (PcdEmbeddedMacBoot)) {
// A MAC will boot in graphics mode, so turn it back to text here
// This protocol was removed from edk2. It is only an edk thing. We need to make our own copy.
// DisableQuietBoot ();
// Enable the biggest output screen size possible
gST->ConOut->SetMode (gST->ConOut, (UINTN)gST->ConOut->Mode->MaxMode - 1);
}
// Save current screen mode
gST->ConOut->QueryMode (gST->ConOut, gST->ConOut->Mode->Mode, &gScreenColumns, &gScreenRows);
EblPrintStartupBanner ();
// Parse command line and handle commands separated by ;
// The loop prints the prompt gets user input and saves history
// Look for a variable with a default command line, otherwise use the Pcd
ZeroMem(&VendorGuid, sizeof(EFI_GUID));
Status = gRT->GetVariable(CommandLineVariableName, &VendorGuid, NULL, &CommandLineVariableSize, CommandLineVariable);
if (Status == EFI_BUFFER_TOO_SMALL) {
CommandLineVariable = AllocatePool(CommandLineVariableSize);
Status = gRT->GetVariable(CommandLineVariableName, &VendorGuid, NULL, &CommandLineVariableSize, CommandLineVariable);
if (!EFI_ERROR(Status)) {
UnicodeStrToAsciiStrS (CommandLineVariable, CmdLine, MAX_CMD_LINE);
}
FreePool(CommandLineVariable);
}
if (EFI_ERROR(Status)) {
AsciiStrCpyS (CmdLine, MAX_CMD_LINE, (CHAR8 *)PcdGetPtr (PcdEmbeddedAutomaticBootCommand));
}
for (;;) {
Status = ProcessCmdLine (CmdLine, MAX_CMD_LINE);
if (Status == EFI_ABORTED) {
// if a command returns EFI_ABORTED then exit the EBL
EblShutdownExternalCmdTable ();
return EFI_SUCCESS;
}
// get the command line from the user
EblPrompt ();
GetCmd (CmdLine, MAX_CMD_LINE);
SetCmdHistory (CmdLine);
if (FeaturePcdGet (PcdEmbeddedProbeRemovable)) {
// Probe removable media devices to see if media has been inserted or removed.
EblProbeRemovableMedia ();
}
}
}