/***
*dospawn.c - spawn a child process
*
* Copyright (c) 1989-2001, Microsoft Corporation. All rights reserved.
*
*Purpose:
* defines _dospawn - spawn a child process
*
*Revision History:
* 06-07-89 PHG Module created, based on asm version
* 03-08-90 GJF Made calling type _CALLTYPE2 (for now), added #include
* <cruntime.h> and fixed the copyright. Also, cleaned
* up the formatting a bit.
* 04-02-90 GJF Now _CALLTYPE1. Added const to type of name arg.
* 07-24-90 SBM Removed '32' from API names
* 09-27-90 GJF New-style function declarator.
* 10-30-90 GJF Added _p_overlay (temporary hack).
* 12-04-90 SRW Changed to include <oscalls.h> instead of <doscalls.h>
* 12-06-90 SRW Added _CRUISER_ and _WIN32 conditionals.
* 01-16-91 SRW Fixed return value for dospawn [_WIN32_]
* 01-17-91 GJF ANSI naming.
* 01-25-91 SRW Changed CreateProcess parameters [_WIN32_]
* 01-29-91 SRW Changed CreateProcess parameters again [_WIN32_]
* 02-05-91 SRW Changed to pass _osfile and _osfhnd arrays as binary
* data to child process. [_WIN32_]
* 02-18-91 SRW Fixed code to return correct process handle and close
* handle for P_WAIT case. [_WIN32_]
* 04-05-91 SRW Fixed code to free StartupInfo.lpReserved2 after
* CreateProcess call. [_WIN32_]
* 04-26-91 SRW Removed level 3 warnings (_WIN32_)
* 12-02-91 SRW Fixed command line setup code to not append an extra
* space [_WIN32_]
* 12-16-91 GJF Return full 32-bit exit code from the child process
* [_WIN32_].
* 02-14-92 GJF Replaced _nfile with _nhandle for Win32.
* 02-18-92 GJF Merged in 12-16-91 change from \\vangogh version
* 11-20-92 SKS errno/_doserrno must be 0 in case of success. This
* will distinguish a child process return code of -1L
* (errno == 0) from an actual error (where errno != 0).
* 01-08-93 CFW Added code to handle _P_DETACH case; add fdwCreate
* variable, nuke stdin, stdout, stderr entries of _osfile
* & _osfhnd tables, close process handle to completely
* detach process
* 04-06-93 SKS Replace _CRTAPI* with __cdecl
* 12-07-93 CFW Rip out Cruiser.
* 12-07-93 CFW Wide char enable, remove _p_overlay.
* 01-05-94 CFW Unremove _p_overlay.
* 01-10-95 CFW Debug CRT allocs.
* 06-12-95 GJF Revised passing of C file handles to work from the
* ioinfo arrays.
* 07-10-95 GJF Use UNALIGNED to avoid choking RISC platforms.
* 05-17-96 GJF Don't pass info on handles marked FNOINHERIT (new
* flag) to the child process.
* 02-05-98 GJF Changes for Win64: return type changed to intptr_t.
* 01-09-00 PML Sign-extend exit code for _P_WAIT on Win64.
* 07-07-01 BWT Return -1 if unable to alloc file ptr table (lpReserved2).
*
*******************************************************************************/
#include <cruntime.h>
#include <oscalls.h>
#include <internal.h>
#include <msdos.h>
#include <process.h>
#include <string.h>
#include <errno.h>
#include <stdlib.h>
#include <tchar.h>
#include <dbgint.h>
#ifndef WPRFLAG
int _p_overlay = 2;
#endif
/***
*int _dospawn(mode, name, cmdblk, envblk) - spawn a child process
*
*Purpose:
* Spawns a child process
*
*Entry:
* int mode - _P_WAIT, _P_NOWAIT, _P_NOWAITO, _P_OVERLAY, or _P_DETACH
* _TSCHAR *name - name of program to execute
* _TSCHAR *cmdblk - parameter block
* _TSCHAR *envblk - environment block
*
*Exit:
* _P_OVERLAY: -1 = error, otherwise doesn't return
* _P_WAIT: termination code << 8 + result code
* _P_DETACH: -1 = error, 0 = success
* others: PID of process
*
*Exceptions:
*
*******************************************************************************/
#ifdef WPRFLAG
intptr_t __cdecl _wdospawn (
#else
intptr_t __cdecl _dospawn (
#endif
int mode,
const _TSCHAR *name,
_TSCHAR *cmdblk,
_TSCHAR *envblk
)
{
char syncexec, asyncresult, background;
LPTSTR CommandLine;
STARTUPINFO StartupInfo;
PROCESS_INFORMATION ProcessInformation;
BOOL CreateProcessStatus;
ULONG dosretval; /* OS return value */
DWORD exitcode;
intptr_t retval;
DWORD fdwCreate = 0; /* flags for CreateProcess */
int i;
ioinfo *pio;
char *posfile;
UNALIGNED intptr_t *posfhnd;
int nh; /* number of file handles to be
passed to the child */
/* translate input mode value to individual flags */
syncexec = asyncresult = background = 0;
switch (mode) {
case _P_WAIT: syncexec=1; break; /* synchronous execution */
case 2: /* _P_OVERLAY */
case _P_NOWAITO: break; /* asynchronous execution */
case _P_NOWAIT: asyncresult=1; break; /* asynch + remember result */
case _P_DETACH: background=1; break; /* detached in null scrn grp */
default:
/* invalid mode */
errno = EINVAL;
_doserrno = 0; /* not a Dos error */
return -1;
}
/*
* Loop over null separate arguments, and replace null separators
* with spaces to turn it back into a single null terminated
* command line.
*/
CommandLine = cmdblk;
while (*cmdblk) {
while (*cmdblk) {
cmdblk++;
}
/*
* If not last argument, turn null separator into a space.
*/
if (cmdblk[1] != _T('\0')) {
*cmdblk++ = _T(' ');
}
}
memset(&StartupInfo,0,sizeof(StartupInfo));
StartupInfo.cb = sizeof(StartupInfo);
for ( nh = _nhandle ;
nh && !_osfile(nh - 1) ;
nh-- ) ;
StartupInfo.cbReserved2 = (WORD)(sizeof( int ) + (nh *
(sizeof( char ) +
sizeof( intptr_t ))));
StartupInfo.lpReserved2 = _calloc_crt( StartupInfo.cbReserved2, 1 );
if (!StartupInfo.lpReserved2) {
errno = ENOMEM;
return -1;
}
*((UNALIGNED int *)(StartupInfo.lpReserved2)) = nh;
for ( i = 0,
posfile = (char *)(StartupInfo.lpReserved2 + sizeof( int )),
posfhnd = (UNALIGNED intptr_t *)(StartupInfo.lpReserved2 +
sizeof( int ) + (nh * sizeof( char ))) ;
i < nh ;
i++, posfile++, posfhnd++ )
{
pio = _pioinfo(i);
if ( (pio->osfile & FNOINHERIT) == 0 ) {
*posfile = pio->osfile;
*posfhnd = pio->osfhnd;
}
else {
*posfile = 0;
*posfhnd = (intptr_t)INVALID_HANDLE_VALUE;
}
}
/*
* if the child process is detached, it cannot access the console, so
* we must nuke the information passed for the first three handles.
*/
if ( background ) {
for ( i = 0,
posfile = (char *)(StartupInfo.lpReserved2 + sizeof( int )),
posfhnd = (UNALIGNED intptr_t *)(StartupInfo.lpReserved2 + sizeof( int )
+ (nh * sizeof( char ))) ;
i < __min( nh, 3 ) ;
i++, posfile++, posfhnd++ )
{
*posfile = 0;
*posfhnd = (intptr_t)INVALID_HANDLE_VALUE;
}
fdwCreate |= DETACHED_PROCESS;
}
/**
* Set errno to 0 to distinguish a child process
* which returns -1L from an error in the spawning
* (which will set errno to something non-zero
**/
_doserrno = errno = 0 ;
#ifdef WPRFLAG
/* indicate to CreateProcess that environment block is wide */
fdwCreate |= CREATE_UNICODE_ENVIRONMENT;
#endif
CreateProcessStatus = CreateProcess( (LPTSTR)name,
CommandLine,
NULL,
NULL,
TRUE,
fdwCreate,
envblk,
NULL,
&StartupInfo,
&ProcessInformation
);
dosretval = GetLastError();
_free_crt( StartupInfo.lpReserved2 );
if (!CreateProcessStatus) {
_dosmaperr(dosretval);
return -1;
}
if (mode == 2 /* _P_OVERLAY */) {
/* destroy ourselves */
_exit(0);
}
else if (mode == _P_WAIT) {
WaitForSingleObject(ProcessInformation.hProcess, (DWORD)(-1L));
/* return termination code and exit code -- note we return
the full exit code */
GetExitCodeProcess(ProcessInformation.hProcess, &exitcode);
retval = (intptr_t)(int)exitcode;
CloseHandle(ProcessInformation.hProcess);
}
else if (mode == _P_DETACH) {
/* like totally detached asynchronous spawn, dude,
close process handle, return 0 for success */
CloseHandle(ProcessInformation.hProcess);
retval = (intptr_t)0;
}
else {
/* asynchronous spawn -- return PID */
retval = (intptr_t)ProcessInformation.hProcess;
}
CloseHandle(ProcessInformation.hThread);
return retval;
}