[frontierkernel-commits] Frontier/Common/source sysshellcall.c,1.3,1.4,

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Update of /cvsroot/frontierkernel/Frontier/Common/source
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv4451/Common/source

Modified Files:
	sysshellcall.c 
Log Message:
Extended winshellcall code to deal with the situation when the COMSPEC environment variable is not defined or does not point to an existing file.

Index: sysshellcall.c
===================================================================
RCS file: /cvsroot/frontierkernel/Frontier/Common/source/sysshellcall.c,v
retrieving revision 1.3
retrieving revision 1.4
diff -C2 -d -r1.3 -r1.4
*** sysshellcall.c	9 Mar 2006 18:37:00 -0000	1.3
--- sysshellcall.c	9 Mar 2006 22:19:54 -0000	1.4
***************
*** 32,35 ****
--- 32,36 ----
  #include "strings.h"
  #include "threads.h"
+ #include "error.h"
  #include "sysshellcall.h"

***************
*** 158,162 ****

  	7.0b51: Call the UNIX popen command, which evaluates a string as if it were typed
! 		ôn the command line. Verb: sys.unixShellCommand.
  		Code adapted by Timothy Paustian from Apple sample code.
  		This routine by PBS.
--- 159,163 ----

  	7.0b51: Call the UNIX popen command, which evaluates a string as if it were typed
! 		on the command line. Verb: sys.unixShellCommand.
  		Code adapted by Timothy Paustian from Apple sample code.
  		This routine by PBS.
***************
*** 207,210 ****
--- 208,263 ----
  #ifdef WIN95VERSION

+ static boolean getenvironmentvariable (char *name, boolean flwinerror, Handle *hresult) {
+ 	
+ 	/*
+ 	2006-03-09 aradke: utility function for getting a Windows environment variable
+ 		as a handle without terminating nil char.
+ 	*/
+ 	
+ 	Handle h;
+ 	long res;
+ 
+ 	res = GetEnvironmentVariable (name, nil, 0);
+ 
+ 	if (res == 0) {
+ 		if (flwinerror)
+ 			winerror ();
+ 		return (false);
+ 		}
+ 
+ 	if (!newclearhandle (res, &h))
+ 		return (false);
+ 
+ 	lockhandle (h);
+ 
+ 	res = GetEnvironmentVariable (name, *h, res);
+ 
+ 	unlockhandle (h);
+ 
+ 	if (!sethandlesize (h, res)) {	/*drop trailing nil char*/
+ 		disposehandle (h);
+ 		return (false);
+ 		}
+ 
+ 	*hresult = h;
+ 		
+ 	return (true);
+ 	} /*getenvironmentvariable*/
+ 
+ 
+ static boolean cmdshellexists (Handle hshell) {
+ 
+ 	DWORD attr;
+ 	
+ 	lockhandle (hshell);
+ 
+ 	attr = GetFileAttributes (*hshell);
+ 
+ 	unlockhandle (hshell);
+ 	
+ 	return (attr != INVALID_FILE_ATTRIBUTES);
+ 	} /*cmdshellexists*/
+ 	
+ 
  static boolean getcmdshell (Handle *hshell) {

***************
*** 216,275 ****
  	*/

! 	Handle h;
! 	long res;
! 
! 	res = GetEnvironmentVariable("COMSPEC", nil, 0);
! 
! 	if (res > 0) { /*var exists, allocate buffer and get its value*/
! 		
! 		if (!newclearhandle (res, &h))
! 			return (false);
! 		
! 		lockhandle (h);

! 		res = GetEnvironmentVariable("COMSPEC", *h, res);	/*FIXME: check result, dispose h*/

! 		unlockhandle (h);

! 		assert (res == gethandlesize (h) - 1);
! 		
! 		sethandlesize (h, res);	/*drop trailing nil char*/
  		}
  	else {
! 		OSVERSIONINFO osinfo;
! 		bigstring bs;

! 		osinfo.dwOSVersionInfoSize = sizeof (osinfo);
! 		
! 		GetVersionEx (&osinfo); /*FIXME: check result, report error*/

! 		if (osinfo.dwPlatformId == VER_PLATFORM_WIN32_WINDOWS) {
! 			copystring ("\x0b" "command.com", bs); /*Win95/98/ME: actual DOS command interpreter*/
  			}
! 		else {
! 			copystring ("\x07" "cmd.exe", bs); /*WinNT and successors: DOS emulation*/
  			}
! 
! 		if (!newtexthandle (bs, &h))
  			return (false);
! 		}	

- 	*hshell = h;
- 
  	return (true);
! 	} /*getcmdshell*/

! boolean runcmdshell (Handle hshell, Handle hcommand, HANDLE *hout) {

  	/*
  	2006-03-09 aradke: launch the command shell as a child process.

  	TO DO:
  		- check length of hcmdline < MAX_PATH
- 		- make sure handles in processinfo struct are closed
- 		- before creating process, check whether hshell exists
- 		- if we can't access hshell, do a search path lookup
- 		- proper error checking and reporting
  	*/

--- 269,419 ----
  	*/

! 	OSVERSIONINFO osinfo;
! 	bigstring bs;
! 	
! 	if (getenvironmentvariable ("COMSPEC", false, hshell))
! 		return (true);

! 	osinfo.dwOSVersionInfoSize = sizeof (osinfo);

! 	if (GetVersionEx (&osinfo) == nil) {
! 		winerror ();
! 		return (false);
! 		}

! 	if (osinfo.dwPlatformId == VER_PLATFORM_WIN32_WINDOWS) {
! 		copystring ("\x0b" "command.com", bs); /*Win95/98/ME: actual DOS command interpreter*/
  		}
  	else {
! 		copystring ("\x07" "cmd.exe", bs); /*WinNT and successors: DOS emulation*/
! 		}

! 	return (newtexthandle (bs, hshell));
! 	} /*getcmdshell*/

! 
! #define CHDOUBLEQUOTE	'"'
! #define CHSEMICOLON		';'
! #define CHBACKSLASH		'\\'
! 
! 
! static boolean getnextpath (Handle hpath, long *ixstart, Handle *hitem) {
! 
! 	Handle h;
! 	handlestream s;
! 	char ch;
! 	
! 	openhandlestream (hpath, &s);
! 	s.pos = *ixstart;
! 	
! 	/*first pass: locate end of next path item*/
! 	
! 	skiphandlestreamchars (&s, CHSEMICOLON); /*ignore leading semicolons*/
! 	*ixstart = s.pos;
! 	
! 	while (!athandlestreameof (&s)) {
! 		
! 		ch = nexthandlestreamcharacter (&s);
! 		
! 		if (ch == CHSEMICOLON) {
! 			break;
  			}
! 		else if (ch == CHDOUBLEQUOTE) {
! 			s.pos++;
! 			seekhandlestreamchar (&s, CHDOUBLEQUOTE); /*skip over contents of doublequotes*/
  			}
! 			
! 		s.pos++;
! 		}/*while*/
! 	
! 	/*extract item*/
! 	
! 	if (!loadfromhandletohandle (s.data, ixstart, s.pos - *ixstart, false, &h))
! 		return (false);
! 	
! 	/*second pass: remove included doublequotes*/
! 	
! 	openhandlestream (h, &s);
! 	
! 	while (true) {
! 		
! 		seekhandlestreamchar (&s, CHDOUBLEQUOTE);
! 		
! 		if (athandlestreameof (&s))
! 			break;
! 		
! 		pullfromhandlestream (&s, 1, nil);
! 		}/*while*/
! 	
! 	if (lasthandlestreamcharacter (&s) != CHBACKSLASH)
! 		if (!writehandlestreamchar (&s, CHBACKSLASH)) {
! 			disposehandlestream (&s);
  			return (false);
! 			}
! 	
! 	*hitem = closehandlestream (&s);

  	return (true);
! 	} /*getnextpath*/
! 	
! 	
! static boolean searchcmdpath (Handle *hshell) {

+ 	/*
+ 	2006-03-09 aradke: get the PATH environment variable and parse it.
+ 		see if the command shell is located in any of the directories.
+ 		caller is responsible for disposing hshell.
+ 	
+ 	TO DO:
+ 		- check length of hshell < MAX_PATH
+ 	*/
+ 	
+ 	Handle hpath = nil;
+ 	Handle h = nil;
+ 	long ix = 0;

! 	/*obtain path environment variable*/
! 
! 	if (!getenvironmentvariable ("PATH", true, &hpath))
! 		return (false);
! 	
! 	/*parse path*/
! 	
! 	while (getnextpath (hpath, &ix, &h)) {
! 		
! 		if (!pushhandle (*hshell, h))
! 			goto exit;
! 		
! 		if (!enlargehandle (h, 1, "\0"))
! 			goto exit;
! 		
! 		if (cmdshellexists (h)) {
! 			disposehandle (*hshell);
! 			*hshell = h;
! 			return (true);
! 			}
! 
! 		disposehandle (h);
! 		}/*while*/
! 	
! 	/*not found*/
! 	
! 	oserror (ERROR_FILE_NOT_FOUND);
! 	
! exit:
! 	disposehandle (hpath);
! 	
! 	return (false);
! 	} /*searchcmdpath*/
! 	
! 	
! static boolean runcmdshell (Handle hshell, Handle hcommand, HANDLE *hout) {

  	/*
  	2006-03-09 aradke: launch the command shell as a child process.
+ 		we consume hshell, but caller is responsible for closing hout if we return true.

  	TO DO:
  		- check length of hcmdline < MAX_PATH
  	*/

***************
*** 280,287 ****
  	HANDLE hpiperead = nil;
  	HANDLE hpipewrite = nil;
- 	DWORD attr;
  	boolean fl;

  	/*create pipe for reading from command shell*/
  	clearbytes (&securityinfo, sizeof (securityinfo));
  	securityinfo.nLength				= sizeof (securityinfo);
--- 424,431 ----
  	HANDLE hpiperead = nil;
  	HANDLE hpipewrite = nil;
  	boolean fl;

  	/*create pipe for reading from command shell*/
+ 
  	clearbytes (&securityinfo, sizeof (securityinfo));
  	securityinfo.nLength				= sizeof (securityinfo);
***************
*** 289,298 ****
  	securityinfo.bInheritHandle			= true;

! 	fl = CreatePipe (&hpiperead, &hpipewrite, &securityinfo, nil);
! 	
! 	if (!fl)
! 		goto exit;

! 	SetHandleInformation (hpiperead, HANDLE_FLAG_INHERIT, 0);

  	/*init structs for creating process*/
--- 433,441 ----
  	securityinfo.bInheritHandle			= true;

! 	if (!CreatePipe (&hpiperead, &hpipewrite, &securityinfo, nil))
! 		goto error;

! 	if (!SetHandleInformation (hpiperead, HANDLE_FLAG_INHERIT, 0))
! 		goto error;

  	/*init structs for creating process*/
***************
*** 324,336 ****
  	/*check whether command shell can be accessed*/

! 	lockhandle (hshell);
! 
! 	attr = GetFileAttributes(*hshell);
! 
! 	unlockhandle (hshell);
! 	
! 	if (attr == INVALID_FILE_ATTRIBUTES)
! 		goto exit; /*not found, try searching PATH for command shell?*/
! 	
  	/*create command shell process*/

--- 467,475 ----
  	/*check whether command shell can be accessed*/

! 	if (!cmdshellexists (hshell)) {
! 		if (!searchcmdpath (&hshell))	/*do a search path lookup*/
! 			goto exit;
! 		}
! 		
  	/*create command shell process*/

***************
*** 356,372 ****

  	if (!fl)
! 		goto exit;

! 	CloseHandle (hpipewrite);	/*inherited by child process*/
  	CloseHandle (processinfo.hProcess);
  	CloseHandle (processinfo.hThread);

  	disposehandle (hcmdline);

  	*hout = hpiperead;

  	return (true);
! 	
! exit:
  	if (!hpiperead)
  		CloseHandle (hpiperead);
--- 495,516 ----

  	if (!fl)
! 		goto error;

! 	CloseHandle (hpipewrite);	/*now inherited by child process*/
! 
  	CloseHandle (processinfo.hProcess);
  	CloseHandle (processinfo.hThread);

  	disposehandle (hcmdline);
+ 	disposehandle (hshell);

  	*hout = hpiperead;

  	return (true);
! 
! error:
! 	winerror (); /*note fall through*/
! 		
! exit:	/*error is already set*/
  	if (!hpiperead)
  		CloseHandle (hpiperead);
***************
*** 376,379 ****
--- 520,524 ----

  	disposehandle (hcmdline);
+ 	disposehandle (hshell);

  	return (false);	
***************
*** 381,389 ****

! boolean readcmdresult (HANDLE hread, Handle hreturn) {

! 	char buf [1024];
  	long ct = 0;
  	boolean fl;

  	while (true) {
--- 526,540 ----

! static boolean readcmdresult (HANDLE hread, Handle hreturn) {
! 
! 	/*
! 	2006-03-09 aradke: read data from pipe until eof.
! 		we close our end of the pipe (hread) whether we succeed or not.
! 	*/

! 	char buf[1024];
  	long ct = 0;
  	boolean fl;
+ 	DWORD err = 0;

  	while (true) {
***************
*** 393,412 ****
  		fl = ReadFile (hread, buf, sizeof (buf), &ct, nil);

! 		grabthreadglobals ();

! 		if (!fl) /*an error occurred*/
! 			break;

! 		if (fl && (ct == 0)) /*end of file*/
  			break;

! 		if (ct > 0)				
! 			if (!enlargehandle (hreturn, ct, buf))
  				break;
  		} /*while*/

  	CloseHandle (hread);

! 	return (true);
  	} /*readcmdresult*/

--- 544,577 ----
  		fl = ReadFile (hread, buf, sizeof (buf), &ct, nil);

! 		if (!fl)
! 			err = GetLastError ();

! 		grabthreadglobals ();

! 		if (fl && (ct == 0)) /*regular end of file*/
  			break;
+ 		
+ 		if (!fl) {
+ 		
+ 			if (err == ERROR_BROKEN_PIPE) 
+ 				fl = true;	/*ignore broken pipe*/
+ 			else
+ 				oserror (err);
+ 			
+ 			break;
+ 			}

! 		if (ct > 0) {
! 		
! 			fl = enlargehandle (hreturn, ct, buf);
! 							
! 			if (!fl)
  				break;
+ 			}
  		} /*while*/

  	CloseHandle (hread);

! 	return (fl);
  	} /*readcmdresult*/

***************
*** 425,445 ****

  	if (!getcmdshell (&hshell))
! 		goto exit;

  	if (!runcmdshell (hshell, hcommand, &hread))
! 		goto exit;

  	if (!readcmdresult (hread, hreturn))
! 		goto exit;
! 
! 	disposehandle (hshell);

  	return (true);
- 
- exit:
- 
- 	disposehandle (hshell);
- 
- 	return (false);
  	} /*winshellcall*/

--- 590,602 ----

  	if (!getcmdshell (&hshell))
! 		return (false);

  	if (!runcmdshell (hshell, hcommand, &hread))
! 		return (false);

  	if (!readcmdresult (hread, hreturn))
! 		return (false);

  	return (true);
  	} /*winshellcall*/

***************
*** 460,464 ****

  	FILE *f;
! 	char buf [1024];
  	long ct = 0;

--- 617,621 ----

  	FILE *f;
! 	char buf[1024];
  	long ct = 0;