cmd.c

PocketCMD是与pocketconsole配合实用的命令行解释器（Shell）

/* $Id: cmd.c,v 1.3 2004/02/16 16:13:36 pfalcon Exp $
 *
 *  CMD.C - command-line interface.
 *
 *
 *  History:
 *
 *    17 Jun 1994 (Tim Norman)
 *        started.
 *
 *    08 Aug 1995 (Matt Rains)
 *        I have cleaned up the source code. changes now bring this source
 *        into guidelines for recommended programming practice.
 *
 *        A added the the standard FreeDOS GNU licence test to the
 *        initialize() function.
 *
 *        Started to replace puts() with printf(). this will help
 *        standardize output. please follow my lead.
 *
 *        I have added some constants to help making changes easier.
 *
 *    15 Dec 1995 (Tim Norman)
 *        major rewrite of the code to make it more efficient and add
 *        redirection support (finally!)
 *
 *    06 Jan 1996 (Tim Norman)
 *        finished adding redirection support!  Changed to use our own
 *        exec code (MUCH thanks to Svante Frey!!)
 *
 *    29 Jan 1996 (Tim Norman)
 *        added support for CHDIR, RMDIR, MKDIR, and ERASE, as per
 *        suggestion of Steffan Kaiser
 *
 *        changed "file not found" error message to "bad command or
 *        filename" thanks to Dustin Norman for noticing that confusing
 *        message!
 *
 *        changed the format to call internal commands (again) so that if
 *        they want to split their commands, they can do it themselves 
 *        (none of the internal functions so far need that much power, anyway)
 *
 *    27 Aug 1996 (Tim Norman)
 *        added in support for Oliver Mueller's ALIAS command
 *
 *    14 Jun 1997 (Steffan Kaiser)
 *        added ctrl-break handling and error level
 *
 *    16 Jun 1998 (Rob Lake)
 *        Runs command.com if /P is specified in command line.  Command.com
 *        also stays permanent.  If /C is in the command line, starts the
 *        program next in the line.
 *
 *    21 Jun 1998 (Rob Lake)
 *        Fixed up /C so that arguments for the program
 *
 *    08-Jul-1998 (John P. Price)
 *        Now sets COMSPEC environment variable
 *        misc clean up and optimization
 *        added date and time commands
 *        changed to using spawnl instead of exec.  exec does not copy the
 *        environment to the child process!
 *
 *    14 Jul 1998 (Hans B Pufal)
 *        Reorganised source to be more efficient and to more closely
 *        follow MS-DOS conventions. (eg %..% environment variable
 *        replacement works form command line as well as batch file.
 *
 *        New organisation also properly support nested batch files.
 *
 *        New command table structure is half way towards providing a
 *        system in which COMMAND will find out what internal commands
 *        are loaded
 *
 *    24 Jul 1998 (Hans B Pufal) [HBP_003]
 *        Fixed return value when called with /C option
 *
 *    27 Jul 1998  John P. Price
 *        added config.h include
 *
 *    28 Jul 1998  John P. Price
 *        added showcmds function to show commands and options available
 *
 *    07-Aug-1998 (John P Price <[e-mail]>)
 *        Fixed carrage return output to better match MSDOS with echo
 *        on or off. (marked with "JPP 19980708")
 *
 *    07-Dec-1998 (Eric Kohl <[e-mail]>)
 *        First ReactOS release.
 *        Extended length of commandline buffers to 512.
 *
 *    13-Dec-1998 (Eric Kohl <[e-mail]>)
 *        Added COMSPEC environment variable.
 *        Added "/t" support (color) on cmd command line.
 *
 *    07-Jan-1999 (Eric Kohl <[e-mail]>)
 *        Added help text ("cmd /?").
 *
 *    25-Jan-1999 (Eric Kohl <[e-mail]>)
 *        Unicode and redirection safe!
 *        Fixed redirections and piping.
 *        Piping is based on temporary files, but basic support
 *        for anonymous pipes already exists.
 *
 *    27-Jan-1999 (Eric Kohl <[e-mail]>)
 *        Replaced spawnl() by CreateProcess().
 *
 *    22-Oct-1999 (Eric Kohl <[e-mail]>)
 *        Added break handler.
 *
 *    15-Dec-1999 (Eric Kohl <[e-mail]>)
 *        Fixed current directory
 *
 *    28-Dec-1999 (Eric Kohl <[e-mail]>)
 *        Restore window title after program/batch execution
 *
 *    03-Feb-2001 (Eric Kohl <[e-mail]>)
 *        Workaround because argc[0] is NULL under ReactOS
 *
 *    23-Feb-2001 (Carl Nettelblad <[e-mail]>)
 *        %envvar% replacement conflicted with for.
 */

#include "config.h"

#include "cmd.h"
#undef fileno
#define fileno _fileno

BOOL GetStdioPathW(DWORD id, PWSTR pwszBuf, LPDWORD lpdwLen);

BOOL bExit = FALSE;       /* indicates EXIT was typed */
BOOL bCanExit = TRUE;     /* indicates if this shell is exitable */
BOOL bCtrlBreak = FALSE;  /* Ctrl-Break or Ctrl-C hit */
BOOL bIgnoreEcho = FALSE; /* Ignore 'newline' before 'cls' */
INT  nErrorLevel = 0;     /* Errorlevel of last launched external program */
BOOL bChildProcessRunning = FALSE;
DWORD dwChildProcessId = 0;
OSVERSIONINFO osvi;

#ifdef INCLUDE_CMD_COLOR
WORD wColor;              /* current color */
WORD wDefColor;           /* default color */
#endif


/*
 *  is character a delimeter when used on first word?
 *
 */

static BOOL IsDelimiter (TCHAR c)
{
	return (c == _T('/') || c == _T('=') || c == _T('\0') || _istspace (c));
}


/*
 * This command (in first) was not found in the command table
 *
 * first - first word on command line
 * rest  - rest of command line
 */

static VOID
Execute (LPTSTR first, LPTSTR rest)
{
	TCHAR szFullName[MAX_PATH];
	TCHAR szWindowTitle[MAX_PATH];
	DWORD dwExitCode = 0;

#ifdef _DEBUG
	DebugPrintf (_T("Execute: \'%s\' \'%s\'\n"), first, rest);
#endif

	/* check for a drive change */
	if ((_istalpha (first[0])) && (!_tcscmp (first + 1, _T(":"))))
	{	
		BOOL working = TRUE;
		if (!SetCurrentDirectory(first))
		/* Guess they changed disc or something, handle that gracefully and get to root */
		{
			TCHAR str[4];
			str[0]=first[0];
			str[1]=_T(':');
			str[2]=_T('\\');
			str[3]=0;
			working = SetCurrentDirectory(str);
		}

		if (!working) ConErrPuts (INVALIDDRIVE);

		return;
	}

	/* get the PATH environment variable and parse it */
	/* search the PATH environment variable for the binary */
	if (!SearchForExecutable (first, szFullName))
	{
		error_bad_command ();
		return;
	}

	GetConsoleTitle (szWindowTitle, MAX_PATH);

	/* check if this is a .BAT or .CMD file */
	if (!_tcsicmp (_tcsrchr (szFullName, _T('.')), _T(".bat")) ||
		!_tcsicmp (_tcsrchr (szFullName, _T('.')), _T(".cmd")))
	{
#ifdef _DEBUG
		DebugPrintf (_T("[BATCH: %s %s]\n"), szFullName, rest);
#endif
		Batch (szFullName, first, rest);
	}
	else
	{
		/* exec the program */
		TCHAR szFullCmdLine [CMDLINE_LENGTH];
		PROCESS_INFORMATION prci;
#ifdef _DEBUG
		DebugPrintf (_T("[EXEC: %s %s]\n"), szFullName, rest);
#endif
		/* build command line for CreateProcess() */
		_tcscpy (szFullCmdLine, szFullName);
		_tcscat (szFullCmdLine, _T(" "));
		_tcscat (szFullCmdLine, rest);
		if (CreateProcess (szFullName,
		                   rest,
		                   NULL,
		                   NULL,
		                   FALSE,
		                   0,
		                   NULL,
		                   NULL,
		                   NULL,
		                   &prci))

		{
			/* FIXME: Protect this with critical section */
			bChildProcessRunning = TRUE;
			dwChildProcessId = prci.dwProcessId;

			WaitForSingleObject (prci.hProcess, INFINITE);

			/* FIXME: Protect this with critical section */
			bChildProcessRunning = TRUE;

			GetExitCodeProcess (prci.hProcess, &dwExitCode);
			nErrorLevel = (INT)dwExitCode;
			CloseHandle (prci.hThread);
			CloseHandle (prci.hProcess);
		}
		else
		{
			ErrorMessage (GetLastError (),
			              _T("Error executing CreateProcess()!!\n"));
		}
	}

	SetConsoleTitle (szWindowTitle);
}


/*
 * look through the internal commands and determine whether or not this
 * command is one of them.  If it is, call the command.  If not, call
 * execute to run it as an external program.
 *
 * line - the command line of the program to run
 *
 */

static VOID
DoCommand (LPTSTR line)
{
	TCHAR com[MAX_PATH];  /* the first word in the command */
	LPTSTR cp = com;
	LPTSTR cstart;
	LPTSTR rest = line;   /* pointer to the rest of the command line */
	INT cl;
	LPCOMMAND cmdptr;

#ifdef _DEBUG
	DebugPrintf (_T("DoCommand: (\'%s\')\n"), line);
#endif /* DEBUG */

	/* Skip over initial white space */
	while (isspace (*rest))
		rest++;

	cstart = rest;

	/* Anything to do ? */
	if (*rest)
	{
		/* Copy over 1st word as lower case */
		while (!IsDelimiter (*rest))
			*cp++ = _totlower (*rest++);

		/* Terminate first word */
		*cp = _T('\0');

		/* Skip over whitespace to rest of line */
		while (_istspace (*rest))
			rest++;

		/* Scan internal command table */
		for (cmdptr = cmds;; cmdptr++)
		{
			/* If end of table execute ext cmd */
			if (cmdptr->name == NULL)
			{
				Execute (com, rest);
				break;
			}

			if (!_tcscmp (com, cmdptr->name))
			{
				cmdptr->func (com, rest);
				break;
			}

			/* The following code handles the case of commands like CD which
			 * are recognised even when the command name and parameter are
			 * not space separated.
			 *
			 * e.g dir..
			 * cd\freda
			 */

			/* Get length of command name */
			cl = _tcslen (cmdptr->name);

			if ((cmdptr->flags & CMD_SPECIAL) &&
			    (!_tcsncmp (cmdptr->name, com, cl)) &&
			    (_tcschr (_T("\\.-"), *(com + cl))))
			{
				/* OK its one of the specials...*/

				/* Terminate first word properly */
				com[cl] = _T('\0');

				/* Call with new rest */
				cmdptr->func (com, cstart + cl);
				break;
			}
		}
	}
}


/*
 * process the command line and execute the appropriate functions
 * full input/output redirection and piping are supported
 */

VOID ParseCommandLine (LPTSTR cmd)
{
	TCHAR cmdline[CMDLINE_LENGTH];
	LPTSTR s;
#ifdef FEATURE_REDIRECTION
	TCHAR in[CMDLINE_LENGTH] = _T("");
	TCHAR out[CMDLINE_LENGTH] = _T("");
	TCHAR err[CMDLINE_LENGTH] = _T("");
	TCHAR szTempPath[MAX_PATH] = _T(".\\");
	TCHAR szFileName[2][MAX_PATH] = {_T(""), _T("")};
	HANDLE hFile[2] = {INVALID_HANDLE_VALUE, INVALID_HANDLE_VALUE};
	LPTSTR t = NULL;
	INT  num = 0;
	INT  nRedirFlags = 0;

	DWORD dwSize;
	WCHAR  szOldConIn[MAX_PATH];
	WCHAR  szOldConOut[MAX_PATH];
	WCHAR  szOldConErr[MAX_PATH];
#endif /* FEATURE_REDIRECTION */

	_tcscpy (cmdline, cmd);
	s = &cmdline[0];

#ifdef _DEBUG
	DebugPrintf (_T("ParseCommandLine: (\'%s\')\n"), s);
#endif /* DEBUG */

#ifdef FEATURE_ALIASES
	/* expand all aliases */
	ExpandAlias (s, CMDLINE_LENGTH);
#endif /* FEATURE_ALIAS */

#ifdef FEATURE_REDIRECTION
	
	/* find the temp path to store temporary files */
	GetTempPath (MAX_PATH, szTempPath);
	if (szTempPath[_tcslen (szTempPath) - 1] != _T('\\'))
		_tcscat (szTempPath, _T("\\"));

	/* get the redirections from the command line */
	num = GetRedirection (s, in, out, err, &nRedirFlags);

	/* more efficient, but do we really need to do this? */
	for (t = in; _istspace (*t); t++)
		;
	_tcscpy (in, t);

	for (t = out; _istspace (*t); t++)
		;
	_tcscpy (out, t);

	for (t = err; _istspace (*t); t++)
		;
	_tcscpy (err, t);

	/* Set up the initial conditions ... */
	/* preserve STDIN, STDOUT and STDERR handles */
	
	GetStdioPathW(0, szOldConIn, &dwSize);
	GetStdioPathW(1, szOldConOut, &dwSize);
	GetStdioPathW(2, szOldConErr, &dwSize);
	
	/* redirect STDIN */
	if (in[0])
	{
		HANDLE hFile = fileno(_wfreopen(in, L"rb", stdin));
		if (hFile == INVALID_HANDLE_VALUE)
		{
			ConErrPrintf (_T("Can't redirect input from file %s\n"), in);
			return;
		}
		

#ifdef _DEBUG
		DebugPrintf (_T("Input redirected from: %s\n"), in);
#endif
	}

	/* Now do all but the last pipe command */
	*szFileName[0] = '\0';
	hFile[0] = INVALID_HANDLE_VALUE;

	while (num-- > 1)
	{
		/* Create unique temporary file name */
		GetTempFileName (szTempPath, _T("CMD"), 0, szFileName[1]);

		/* Set current stdout to temporary file */
		hFile[1] = fileno(_wfreopen(szFileName[1], L"wb", stdout));

		DoCommand (s);

		/* close stdout file */
		_wfreopen(szOldConOut, L"wb", stdout);
		hFile[1] = INVALID_HANDLE_VALUE;

		/* close old stdin file */
		_wfreopen(szOldConIn, L"rb", stdin);
		if ((hFile[0] != INVALID_HANDLE_VALUE) && wcscmp(szFileName[0], szOldConIn))
		{
			/* delete old stdin file, if it is a real file */
			hFile[0] = INVALID_HANDLE_VALUE;
			DeleteFile (szFileName[0]);
			*szFileName[0] = _T('\0');
		}

		/* copy stdout file name to stdin file name */
		_tcscpy (szFileName[0], szFileName[1]);
		*szFileName[1] = _T('\0');

		/* open new stdin file */
		hFile[0] = fileno(_wfreopen(szFileName[0], L"rb", stdin));

		s = s + _tcslen (s) + 1;
	}

	/* Now set up the end conditions... */
	/* redirect STDOUT */
	if (out[0])
	{
		/* Final output to here */
		FILE *file;

		if (nRedirFlags & OUTPUT_APPEND) 
		  file = _wfreopen(out, L"ab", stdout);
		else
		  file = _wfreopen(out, L"wb", stdout);

		if (!file)
		{
			ConErrPrintf (_T("Can't redirect to file %s\n"), out);
			return;
		}

#ifdef _DEBUG
		DebugPrintf (_T("Output redirected to: %s\n"), out);
#endif
	}
	else if (*szOldConOut)
	{
		/* Restore original stdout */
		WCHAR szOut[MAX_PATH];
		GetStdioPathW (STD_OUTPUT_HANDLE, szOut, &dwSize);
		_wfreopen( szOldConOut, L"wb", stdout);
	}

	/* redirect STDERR */
	
	if (err[0])
	{
		/* Final output to here */
		FILE *file;

		if (!_tcscmp (err, out))