w32/subproc/sub_proc.c

/* Process handling for Windows.
Copyright (C) 1996-2012 Free Software Foundation, Inc.
This file is part of GNU Make.

GNU Make is free software; you can redistribute it and/or modify it under the
terms of the GNU General Public License as published by the Free Software
Foundation; either version 3 of the License, or (at your option) any later
version.

GNU Make is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
A PARTICULAR PURPOSE.  See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with
this program.  If not, see <http://www.gnu.org/licenses/>.  */

#include <config.h>
#include <stdlib.h>
#include <stdio.h>
#ifdef _MSC_VER
# include <stddef.h>    /* for intptr_t */
#else
# include <stdint.h>
#endif
#include <process.h>  /* for msvc _beginthreadex, _endthreadex */
#include <signal.h>
#include <windows.h>

#include "sub_proc.h"
#include "proc.h"
#include "w32err.h"
#include "debug.h"

static char *make_command_line(char *shell_name, char *exec_path, char **argv);
extern char *xmalloc (unsigned int);

typedef struct sub_process_t {
	intptr_t sv_stdin[2];
	intptr_t sv_stdout[2];
	intptr_t sv_stderr[2];
	int using_pipes;
	char *inp;
	DWORD incnt;
	char * volatile outp;
	volatile DWORD outcnt;
	char * volatile errp;
	volatile DWORD errcnt;
	pid_t pid;
	int exit_code;
	int signal;
	long last_err;
	long lerrno;
} sub_process;

/* keep track of children so we can implement a waitpid-like routine */
static sub_process *proc_array[MAXIMUM_WAIT_OBJECTS];
static int proc_index = 0;
static int fake_exits_pending = 0;

/* Windows jobserver implementation variables */
static char jobserver_semaphore_name[MAX_PATH + 1];
static HANDLE jobserver_semaphore = NULL;

/* Open existing jobserver semaphore */
int open_jobserver_semaphore(const char* name)
{
    jobserver_semaphore = OpenSemaphore(
        SEMAPHORE_ALL_ACCESS,	// Semaphore access setting
        FALSE,			// Child processes DON'T inherit
        name);			// Semaphore name

    if (jobserver_semaphore == NULL)
        return 0;

    return 1;        
}

/* Create new jobserver semaphore */
int create_jobserver_semaphore(int tokens)
{
    sprintf(jobserver_semaphore_name, "gmake_semaphore_%d", _getpid());

    jobserver_semaphore = CreateSemaphore(
        NULL, 				// Use default security descriptor
        tokens,				// Initial count
        tokens, 			// Maximum count
        jobserver_semaphore_name);	// Semaphore name

    if (jobserver_semaphore == NULL)
        return 0;

    return 1;        
}

/* Close jobserver semaphore */
void free_jobserver_semaphore()
{
    if (jobserver_semaphore != NULL)
    {
        CloseHandle(jobserver_semaphore);
        jobserver_semaphore = NULL;
    }
}

/* Decrement semaphore count */
int acquire_jobserver_semaphore()
{
    DWORD dwEvent = WaitForSingleObject(
        jobserver_semaphore,	// Handle to semaphore
        0);			// DON'T wait on semaphore

    return (dwEvent == WAIT_OBJECT_0);
}

/* Increment semaphore count */
int release_jobserver_semaphore()
{
    BOOL bResult = ReleaseSemaphore( 
        jobserver_semaphore,  	// handle to semaphore
        1,            		// increase count by one
        NULL);        		// not interested in previous count

    return (bResult);
}

int has_jobserver_semaphore()
{
    return (jobserver_semaphore != NULL);
}

char* get_jobserver_semaphore_name()
{
    return (jobserver_semaphore_name);
}

/* Wait for either the jobserver semaphore to become signalled or one of our
 * child processes to terminate.
 */
int wait_for_semaphore_or_child_process()
{
    HANDLE handles[MAXIMUM_WAIT_OBJECTS];
    DWORD dwHandleCount = 1;
    DWORD dwEvent;
    int i;

    /* Add jobserver semaphore to first slot. */
    handles[0] = jobserver_semaphore;

    /* Build array of handles to wait for */
    for (i = 0; i < proc_index; i++) 
    {
        /* Don't wait on child processes that have already finished */
        if (fake_exits_pending && proc_array[i]->exit_code)
            continue;

        handles[dwHandleCount++] = (HANDLE) proc_array[i]->pid;
    }

    dwEvent = WaitForMultipleObjects( 
        dwHandleCount,	// number of objects in array
        handles,	// array of objects
        FALSE,		// wait for any object
        INFINITE);	// wait until object is signalled

    switch(dwEvent)
    {
      case WAIT_FAILED:
        return -1;

      case WAIT_OBJECT_0:
        /* Indicate that the semaphore was signalled */
        return 1;

      default:
        /* Assume that one or more of the child processes terminated. */
        return 0;
    }
}

/*
 * When a process has been waited for, adjust the wait state
 * array so that we don't wait for it again
 */
static void
process_adjust_wait_state(sub_process* pproc)
{
	int i;

	if (!proc_index)
		return;

	for (i = 0; i < proc_index; i++)
		if (proc_array[i]->pid == pproc->pid)
			break;

	if (i < proc_index) {
		proc_index--;
		if (i != proc_index)
			memmove(&proc_array[i], &proc_array[i+1],
				(proc_index-i) * sizeof(sub_process*));
		proc_array[proc_index] = NULL;
	}
}

/*
 * Waits for any of the registered child processes to finish.
 */
static sub_process *
process_wait_for_any_private(int block, DWORD* pdwWaitStatus)
{
	HANDLE handles[MAXIMUM_WAIT_OBJECTS];
	DWORD retval, which;
	int i;

	if (!proc_index)
		return NULL;

	/* build array of handles to wait for */
	for (i = 0; i < proc_index; i++) {
		handles[i] = (HANDLE) proc_array[i]->pid;

		if (fake_exits_pending && proc_array[i]->exit_code)
			break;
	}

	/* wait for someone to exit */
	if (!fake_exits_pending) {
		retval = WaitForMultipleObjects(proc_index, handles, FALSE, (block ? INFINITE : 0));
		which = retval - WAIT_OBJECT_0;
	} else {
		fake_exits_pending--;
		retval = !WAIT_FAILED;
		which = i;
	}

        /* If the pointer is not NULL, set the wait status result variable. */
        if (pdwWaitStatus)
            *pdwWaitStatus = retval;

	/* return pointer to process */
        if ((retval == WAIT_TIMEOUT) || (retval == WAIT_FAILED)) {
		return NULL;
        }
	else {
		sub_process* pproc = proc_array[which];
		process_adjust_wait_state(pproc);
		return pproc;
	} 
}

/*
 * Terminate a process.
 */
BOOL
process_kill(HANDLE proc, int signal)
{
	sub_process* pproc = (sub_process*) proc;
	pproc->signal = signal;
	return (TerminateProcess((HANDLE) pproc->pid, signal));
}

/*
 * Use this function to register processes you wish to wait for by
 * calling process_file_io(NULL) or process_wait_any(). This must be done
 * because it is possible for callers of this library to reuse the same
 * handle for multiple processes launches :-(
 */
void
process_register(HANDLE proc)
{
	if (proc_index < MAXIMUM_WAIT_OBJECTS)
		proc_array[proc_index++] = (sub_process *) proc;
}

/*
 * Return the number of processes that we are still waiting for.
 */
int
process_used_slots(void)
{
	return proc_index;
}

/*
 * Public function which works kind of like waitpid(). Wait for any
 * of the children to die and return results. To call this function,
 * you must do 1 of things:
 *
 * 	x = process_easy(...);
 *
 * or
 *
 *	x = process_init_fd();
 *	process_register(x);
 *
 * or
 *
 *	x = process_init();
 *	process_register(x);
 *
 * You must NOT then call process_pipe_io() because this function is
 * not capable of handling automatic notification of any child
 * death.
 */

HANDLE
process_wait_for_any(int block, DWORD* pdwWaitStatus)
{
	sub_process* pproc = process_wait_for_any_private(block, pdwWaitStatus);

	if (!pproc)
		return NULL;
	else {
		/*
		 * Ouch! can't tell caller if this fails directly. Caller
		 * will have to use process_last_err()
                 */
		(void) process_file_io(pproc);
		return ((HANDLE) pproc);
	}
}

long
process_signal(HANDLE proc)
{
        if (proc == INVALID_HANDLE_VALUE) return 0;
        return (((sub_process *)proc)->signal);
}

long
process_last_err(HANDLE proc)
{
        if (proc == INVALID_HANDLE_VALUE) return ERROR_INVALID_HANDLE;
	return (((sub_process *)proc)->last_err);
}

long
process_exit_code(HANDLE proc)
{
        if (proc == INVALID_HANDLE_VALUE) return EXIT_FAILURE;
	return (((sub_process *)proc)->exit_code);
}

/*
2006-02:
All the following functions are currently unused.
All of them would crash gmake if called with argument INVALID_HANDLE_VALUE.
Hence whoever wants to use one of this functions must invent and implement
a reasonable error handling for this function.

char *
process_outbuf(HANDLE proc)
{
	return (((sub_process *)proc)->outp);
}

char *
process_errbuf(HANDLE proc)
{
	return (((sub_process *)proc)->errp);
}

int
process_outcnt(HANDLE proc)
{
	return (((sub_process *)proc)->outcnt);
}

int
process_errcnt(HANDLE proc)
{
	return (((sub_process *)proc)->errcnt);
}

void
process_pipes(HANDLE proc, int pipes[3])
{
	pipes[0] = ((sub_process *)proc)->sv_stdin[0];
	pipes[1] = ((sub_process *)proc)->sv_stdout[0];
	pipes[2] = ((sub_process *)proc)->sv_stderr[0];
	return;
}
*/

	HANDLE
process_init()
{
	sub_process *pproc;
	/*
	 * open file descriptors for attaching stdin/stdout/sterr
	 */
	HANDLE stdin_pipes[2];
	HANDLE stdout_pipes[2];
	HANDLE stderr_pipes[2];
	SECURITY_ATTRIBUTES inherit;
	BYTE sd[SECURITY_DESCRIPTOR_MIN_LENGTH];

	pproc = malloc(sizeof(*pproc));
	memset(pproc, 0, sizeof(*pproc));

	/* We can't use NULL for lpSecurityDescriptor because that
	   uses the default security descriptor of the calling process.
	   Instead we use a security descriptor with no DACL.  This
	   allows nonrestricted access to the associated objects. */

	if (!InitializeSecurityDescriptor((PSECURITY_DESCRIPTOR)(&sd),
					  SECURITY_DESCRIPTOR_REVISION)) {
		pproc->last_err = GetLastError();
		pproc->lerrno = E_SCALL;
		return((HANDLE)pproc);
	}

	inherit.nLength = sizeof(inherit);
	inherit.lpSecurityDescriptor = (PSECURITY_DESCRIPTOR)(&sd);
	inherit.bInheritHandle = TRUE;

	// By convention, parent gets pipe[0], and child gets pipe[1]
	// This means the READ side of stdin pipe goes into pipe[1]
	// and the WRITE side of the stdout and stderr pipes go into pipe[1]
	if (CreatePipe( &stdin_pipes[1], &stdin_pipes[0], &inherit, 0) == FALSE ||
	CreatePipe( &stdout_pipes[0], &stdout_pipes[1], &inherit, 0) == FALSE ||
	CreatePipe( &stderr_pipes[0], &stderr_pipes[1], &inherit, 0) == FALSE) {

		pproc->last_err = GetLastError();
		pproc->lerrno = E_SCALL;
		return((HANDLE)pproc);
	}

	//
	// Mark the parent sides of the pipes as non-inheritable
	//
	if (SetHandleInformation(stdin_pipes[0],
				HANDLE_FLAG_INHERIT, 0) == FALSE ||
		SetHandleInformation(stdout_pipes[0],
				HANDLE_FLAG_INHERIT, 0) == FALSE ||
		SetHandleInformation(stderr_pipes[0],
				HANDLE_FLAG_INHERIT, 0) == FALSE) {

		pproc->last_err = GetLastError();
		pproc->lerrno = E_SCALL;
		return((HANDLE)pproc);
	}
	pproc->sv_stdin[0]  = (intptr_t) stdin_pipes[0];
	pproc->sv_stdin[1]  = (intptr_t) stdin_pipes[1];
	pproc->sv_stdout[0] = (intptr_t) stdout_pipes[0];
	pproc->sv_stdout[1] = (intptr_t) stdout_pipes[1];
	pproc->sv_stderr[0] = (intptr_t) stderr_pipes[0];
	pproc->sv_stderr[1] = (intptr_t) stderr_pipes[1];

	pproc->using_pipes = 1;

	pproc->lerrno = 0;

	return((HANDLE)pproc);
}


	HANDLE
process_init_fd(HANDLE stdinh, HANDLE stdouth, HANDLE stderrh)
{
	sub_process *pproc;

	pproc = malloc(sizeof(*pproc));
	if (pproc) {
		memset(pproc, 0, sizeof(*pproc));

		/*
		 * Just pass the provided file handles to the 'child
		 * side' of the pipe, bypassing pipes altogether.
		 */
		pproc->sv_stdin[1]  = (intptr_t) stdinh;
		pproc->sv_stdout[1] = (intptr_t) stdouth;
		pproc->sv_stderr[1] = (intptr_t) stderrh;

		pproc->last_err = pproc->lerrno = 0;
	}

	return((HANDLE)pproc);
}


static HANDLE
find_file(const char *exec_path, const char *path_var,
	  char *full_fname, DWORD full_len)
{
	HANDLE exec_handle;
	char *fname;
	char *ext;
	DWORD req_len;
	int i;
	static const char *extensions[] =
	  /* Should .com come before no-extension case?  */
	  { ".exe", ".cmd", ".bat", "", ".com", NULL };

	fname = xmalloc(strlen(exec_path) + 5);
	strcpy(fname, exec_path);
	ext = fname + strlen(fname);

	for (i = 0; extensions[i]; i++) {
		strcpy(ext, extensions[i]);
		if (((req_len = SearchPath (path_var, fname, NULL, full_len,
					    full_fname, NULL)) > 0
		     /* For compatibility with previous code, which
			used OpenFile, and with Windows operation in
			general, also look in various default
			locations, such as Windows directory and
			Windows System directory.  Warning: this also
			searches PATH in the Make's environment, which
			might not be what the Makefile wants, but it
			seems to be OK as a fallback, after the
			previous SearchPath failed to find on child's
			PATH.  */
		     || (req_len = SearchPath (NULL, fname, NULL, full_len,
					       full_fname, NULL)) > 0)
		    && req_len <= full_len
		    && (exec_handle =
				CreateFile(full_fname,
					   GENERIC_READ,
					   FILE_SHARE_READ | FILE_SHARE_WRITE,
					   NULL,
					   OPEN_EXISTING,
					   FILE_ATTRIBUTE_NORMAL,
					   NULL)) != INVALID_HANDLE_VALUE) {
			free(fname);
			return(exec_handle);
		}
	}

	free(fname);
	return INVALID_HANDLE_VALUE;
}


/*
 * Description:   Create the child process to be helped
 *
 * Returns: success <=> 0
 *
 * Notes/Dependencies:
 */
long
process_begin(
	HANDLE proc,
	char **argv,
	char **envp,
	char *exec_path,
	char *as_user)
{
	sub_process *pproc = (sub_process *)proc;
	char *shell_name = 0;
	int file_not_found=0;
	HANDLE exec_handle;
	char exec_fname[MAX_PATH];
	const char *path_var = NULL;
	char **ep;
	char buf[256];
	DWORD bytes_returned;
	DWORD flags;
	char *command_line;
	STARTUPINFO startInfo;
	PROCESS_INFORMATION procInfo;
	char *envblk=NULL;

	/*
	 *  Shell script detection...  if the exec_path starts with #! then
	 *  we want to exec shell-script-name exec-path, not just exec-path
	 *  NT doesn't recognize #!/bin/sh or #!/etc/Tivoli/bin/perl.  We do not
	 *  hard-code the path to the shell or perl or whatever:  Instead, we
	 *  assume it's in the path somewhere (generally, the NT tools
	 *  bin directory)
	 */

	/* Use the Makefile's value of PATH to look for the program to
	   execute, because it could be different from Make's PATH
	   (e.g., if the target sets its own value.  */
	if (envp)
		for (ep = envp; *ep; ep++) {
			if (strncmp (*ep, "PATH=", 5) == 0
			    || strncmp (*ep, "Path=", 5) == 0) {
				path_var = *ep + 5;
				break;
			}
		}
	exec_handle = find_file(exec_path, path_var,
				exec_fname, sizeof(exec_fname));

	/*
	 * If we couldn't open the file, just assume that Windows will be
	 * somehow able to find and execute it.
	 */
	if (exec_handle == INVALID_HANDLE_VALUE) {
		file_not_found++;
	}
	else {
		/* Attempt to read the first line of the file */
		if (ReadFile( exec_handle,
				buf, sizeof(buf) - 1, /* leave room for trailing NULL */
				&bytes_returned, 0) == FALSE || bytes_returned < 2) {

			pproc->last_err = GetLastError();
			pproc->lerrno = E_IO;
			CloseHandle(exec_handle);
			return(-1);
		}
		if (buf[0] == '#' && buf[1] == '!') {
			/*
			 *  This is a shell script...  Change the command line from
			 *	exec_path args to shell_name exec_path args
			 */
			char *p;

			/*  Make sure buf is NULL terminated */
			buf[bytes_returned] = 0;
			/*
			 * Depending on the file system type, etc. the first line
			 * of the shell script may end with newline or newline-carriage-return
			 * Whatever it ends with, cut it off.
			 */
			p= strchr(buf, '\n');
			if (p)
				*p = 0;
			p = strchr(buf, '\r');
			if (p)
				*p = 0;

			/*
			 *  Find base name of shell
			 */
			shell_name = strrchr( buf, '/');
			if (shell_name) {
				shell_name++;
			} else {
				shell_name = &buf[2];/* skipping "#!" */
			}

		}
		CloseHandle(exec_handle);
	}

	flags = 0;

	if (file_not_found)
		command_line = make_command_line( shell_name, exec_path, argv);
	else
		command_line = make_command_line( shell_name, exec_fname, argv);

	if ( command_line == NULL ) {
		pproc->last_err = 0;
		pproc->lerrno = E_NO_MEM;
		return(-1);
	}

	if (envp) {
		if (arr2envblk(envp, &envblk) ==FALSE) {
			pproc->last_err = 0;
			pproc->lerrno = E_NO_MEM;
			free( command_line );
			return(-1);
		}
	}

	if ((shell_name) || (file_not_found)) {
		exec_path = 0;	/* Search for the program in %Path% */
	} else {
		exec_path = exec_fname;
	}

	/*
	 *  Set up inherited stdin, stdout, stderr for child
	 */
	GetStartupInfo(&startInfo);
	startInfo.dwFlags = STARTF_USESTDHANDLES;
	startInfo.lpReserved = 0;
	startInfo.cbReserved2 = 0;
	startInfo.lpReserved2 = 0;
	startInfo.lpTitle = shell_name ? shell_name : exec_path;
	startInfo.hStdInput = (HANDLE)pproc->sv_stdin[1];
	startInfo.hStdOutput = (HANDLE)pproc->sv_stdout[1];
	startInfo.hStdError = (HANDLE)pproc->sv_stderr[1];

	if (as_user) {
		if (envblk) free(envblk);
		return -1;
	} else {
		DB (DB_JOBS, ("CreateProcess(%s,%s,...)\n",
			exec_path ? exec_path : "NULL",
			command_line ? command_line : "NULL"));
		if (CreateProcess(
			exec_path,
			command_line,
			NULL,
			0, /* default security attributes for thread */
			TRUE, /* inherit handles (e.g. helper pipes, oserv socket) */
			flags,
			envblk,
			0, /* default starting directory */
			&startInfo,
			&procInfo) == FALSE) {

			pproc->last_err = GetLastError();
			pproc->lerrno = E_FORK;
			fprintf(stderr, "process_begin: CreateProcess(%s, %s, ...) failed.\n",
                                exec_path ? exec_path : "NULL", command_line);
			if (envblk) free(envblk);
			free( command_line );
			return(-1);
		}
	}

	pproc->pid = (pid_t)procInfo.hProcess;
	/* Close the thread handle -- we'll just watch the process */
	CloseHandle(procInfo.hThread);

	/* Close the halves of the pipes we don't need */
	if ((HANDLE)pproc->sv_stdin[1] != INVALID_HANDLE_VALUE)
	  CloseHandle((HANDLE)pproc->sv_stdin[1]);
	if ((HANDLE)pproc->sv_stdout[1] != INVALID_HANDLE_VALUE)
	  CloseHandle((HANDLE)pproc->sv_stdout[1]);
	if ((HANDLE)pproc->sv_stderr[1] != INVALID_HANDLE_VALUE)
	  CloseHandle((HANDLE)pproc->sv_stderr[1]);
        pproc->sv_stdin[1] = 0;
        pproc->sv_stdout[1] = 0;
        pproc->sv_stderr[1] = 0;

	free( command_line );
	if (envblk) free(envblk);
	pproc->lerrno=0;
	return 0;
}



#if 0	/* unused */
static DWORD
proc_stdin_thread(sub_process *pproc)
{
	DWORD in_done;
	for (;;) {
		if (WriteFile( (HANDLE) pproc->sv_stdin[0], pproc->inp, pproc->incnt,
					 &in_done, NULL) == FALSE)
			_endthreadex(0);
		// This if should never be true for anonymous pipes, but gives
		// us a chance to change I/O mechanisms later
		if (in_done < pproc->incnt) {
			pproc->incnt -= in_done;
			pproc->inp += in_done;
		} else {
			_endthreadex(0);
		}
	}
	return 0; // for compiler warnings only.. not reached
}

static DWORD
proc_stdout_thread(sub_process *pproc)
{
	DWORD bufsize = 1024;
	char c;
	DWORD nread;
	pproc->outp = malloc(bufsize);
	if (pproc->outp == NULL)
		_endthreadex(0);
	pproc->outcnt = 0;

	for (;;) {
		if (ReadFile( (HANDLE)pproc->sv_stdout[0], &c, 1, &nread, NULL)
					== FALSE) {
/*			map_windows32_error_to_string(GetLastError());*/
			_endthreadex(0);
		}
		if (nread == 0)
			_endthreadex(0);
		if (pproc->outcnt + nread > bufsize) {
			bufsize += nread + 512;
			pproc->outp = realloc(pproc->outp, bufsize);
			if (pproc->outp == NULL) {
				pproc->outcnt = 0;
				_endthreadex(0);
			}
		}
		pproc->outp[pproc->outcnt++] = c;
	}
	return 0;
}

static DWORD
proc_stderr_thread(sub_process *pproc)
{
	DWORD bufsize = 1024;
	char c;
	DWORD nread;
	pproc->errp = malloc(bufsize);
	if (pproc->errp == NULL)
		_endthreadex(0);
	pproc->errcnt = 0;

	for (;;) {
		if (ReadFile( (HANDLE)pproc->sv_stderr[0], &c, 1, &nread, NULL) == FALSE) {
			map_windows32_error_to_string(GetLastError());
			_endthreadex(0);
		}
		if (nread == 0)
			_endthreadex(0);
		if (pproc->errcnt + nread > bufsize) {
			bufsize += nread + 512;
			pproc->errp = realloc(pproc->errp, bufsize);
			if (pproc->errp == NULL) {
				pproc->errcnt = 0;
				_endthreadex(0);
			}
		}
		pproc->errp[pproc->errcnt++] = c;
	}
	return 0;
}


/*
 * Purpose: collects output from child process and returns results
 *
 * Description:
 *
 * Returns:
 *
 * Notes/Dependencies:
 */
	long
process_pipe_io(
	HANDLE proc,
	char *stdin_data,
	int stdin_data_len)
{
	sub_process *pproc = (sub_process *)proc;
	bool_t stdin_eof = FALSE, stdout_eof = FALSE, stderr_eof = FALSE;
	HANDLE childhand = (HANDLE) pproc->pid;
	HANDLE tStdin = NULL, tStdout = NULL, tStderr = NULL;
	unsigned int dwStdin, dwStdout, dwStderr;
	HANDLE wait_list[4];
	DWORD wait_count;
	DWORD wait_return;
	HANDLE ready_hand;
	bool_t child_dead = FALSE;
	BOOL GetExitCodeResult;

	/*
	 *  Create stdin thread, if needed
	 */
	pproc->inp = stdin_data;
	pproc->incnt = stdin_data_len;
	if (!pproc->inp) {
		stdin_eof = TRUE;
		CloseHandle((HANDLE)pproc->sv_stdin[0]);
		pproc->sv_stdin[0] = 0;
	} else {
		tStdin = (HANDLE) _beginthreadex( 0, 1024,
			(unsigned (__stdcall *) (void *))proc_stdin_thread,
						  pproc, 0, &dwStdin);
		if (tStdin == 0) {
			pproc->last_err = GetLastError();
			pproc->lerrno = E_SCALL;
			goto done;
		}
	}

	/*
	 *   Assume child will produce stdout and stderr
	 */
	tStdout = (HANDLE) _beginthreadex( 0, 1024,
		(unsigned (__stdcall *) (void *))proc_stdout_thread, pproc, 0,
		&dwStdout);
	tStderr = (HANDLE) _beginthreadex( 0, 1024,
		(unsigned (__stdcall *) (void *))proc_stderr_thread, pproc, 0,
		&dwStderr);

	if (tStdout == 0 || tStderr == 0) {

		pproc->last_err = GetLastError();
		pproc->lerrno = E_SCALL;
		goto done;
	}


	/*
	 *  Wait for all I/O to finish and for the child process to exit
	 */

	while (!stdin_eof || !stdout_eof || !stderr_eof || !child_dead) {
		wait_count = 0;
		if (!stdin_eof) {
			wait_list[wait_count++] = tStdin;
		}
		if (!stdout_eof) {
			wait_list[wait_count++] = tStdout;
		}
		if (!stderr_eof) {
			wait_list[wait_count++] = tStderr;
		}
		if (!child_dead) {
			wait_list[wait_count++] = childhand;
		}

		wait_return = WaitForMultipleObjects(wait_count, wait_list,
			 FALSE, /* don't wait for all: one ready will do */
			 child_dead? 1000 :INFINITE); /* after the child dies, subthreads have
			 	one second to collect all remaining output */

		if (wait_return == WAIT_FAILED) {
/*			map_windows32_error_to_string(GetLastError());*/
			pproc->last_err = GetLastError();
			pproc->lerrno = E_SCALL;
			goto done;
		}

		ready_hand = wait_list[wait_return - WAIT_OBJECT_0];

		if (ready_hand == tStdin) {
			CloseHandle((HANDLE)pproc->sv_stdin[0]);
			pproc->sv_stdin[0] = 0;
			CloseHandle(tStdin);
			tStdin = 0;
			stdin_eof = TRUE;

		} else if (ready_hand == tStdout) {

		  	CloseHandle((HANDLE)pproc->sv_stdout[0]);
			pproc->sv_stdout[0] = 0;
			CloseHandle(tStdout);
			tStdout = 0;
		  	stdout_eof = TRUE;

		} else if (ready_hand == tStderr) {

			CloseHandle((HANDLE)pproc->sv_stderr[0]);
			pproc->sv_stderr[0] = 0;
			CloseHandle(tStderr);
			tStderr = 0;
			stderr_eof = TRUE;

		} else if (ready_hand == childhand) {

			DWORD ierr;
			GetExitCodeResult = GetExitCodeProcess(childhand, &ierr);
			if (ierr == CONTROL_C_EXIT) {
				pproc->signal = SIGINT;
			} else {
				pproc->exit_code = ierr;
			}
			if (GetExitCodeResult == FALSE) {
				pproc->last_err = GetLastError();
				pproc->lerrno = E_SCALL;
				goto done;
			}
			child_dead = TRUE;

		} else {

			/* ?? Got back a handle we didn't query ?? */
			pproc->last_err = 0;
			pproc->lerrno = E_FAIL;
			goto done;
		}
	}

 done:
	if (tStdin != 0)
		CloseHandle(tStdin);
	if (tStdout != 0)
		CloseHandle(tStdout);
	if (tStderr != 0)
		CloseHandle(tStderr);

	if (pproc->lerrno)
		return(-1);
	else
		return(0);

}
#endif	/* unused */

/*
 * Purpose: collects output from child process and returns results
 *
 * Description:
 *
 * Returns:
 *
 * Notes/Dependencies:
 */
	long
process_file_io(
	HANDLE proc)
{
	sub_process *pproc;
	HANDLE childhand;
	DWORD wait_return;
	BOOL GetExitCodeResult;
        DWORD ierr;

	if (proc == NULL)
		pproc = process_wait_for_any_private(1, 0);
	else
		pproc = (sub_process *)proc;

	/* some sort of internal error */
	if (!pproc)
		return -1;

	childhand = (HANDLE) pproc->pid;

	/*
	 * This function is poorly named, and could also be used just to wait
	 * for child death if you're doing your own pipe I/O.  If that is
	 * the case, close the pipe handles here.
	 */
	if (pproc->sv_stdin[0]) {
		CloseHandle((HANDLE)pproc->sv_stdin[0]);
		pproc->sv_stdin[0] = 0;
	}
	if (pproc->sv_stdout[0]) {
		CloseHandle((HANDLE)pproc->sv_stdout[0]);
		pproc->sv_stdout[0] = 0;
	}
	if (pproc->sv_stderr[0]) {
		CloseHandle((HANDLE)pproc->sv_stderr[0]);
		pproc->sv_stderr[0] = 0;
	}

	/*
	 *  Wait for the child process to exit
	 */

	wait_return = WaitForSingleObject(childhand, INFINITE);

	if (wait_return != WAIT_OBJECT_0) {
/*		map_windows32_error_to_string(GetLastError());*/
		pproc->last_err = GetLastError();
		pproc->lerrno = E_SCALL;
		goto done2;
	}

	GetExitCodeResult = GetExitCodeProcess(childhand, &ierr);
	if (ierr == CONTROL_C_EXIT) {
		pproc->signal = SIGINT;
	} else {
		pproc->exit_code = ierr;
	}
	if (GetExitCodeResult == FALSE) {
		pproc->last_err = GetLastError();
		pproc->lerrno = E_SCALL;
	}

done2:
	if (pproc->lerrno)
		return(-1);
	else
		return(0);

}

/*
 * Description:  Clean up any leftover handles, etc.  It is up to the
 * caller to manage and free the input, ouput, and stderr buffers.
 */
	void
process_cleanup(
	HANDLE proc)
{
	sub_process *pproc = (sub_process *)proc;
	int i;

	if (pproc->using_pipes) {
		for (i= 0; i <= 1; i++) {
			if ((HANDLE)pproc->sv_stdin[i]
			    && (HANDLE)pproc->sv_stdin[i] != INVALID_HANDLE_VALUE)
				CloseHandle((HANDLE)pproc->sv_stdin[i]);
			if ((HANDLE)pproc->sv_stdout[i]
			    && (HANDLE)pproc->sv_stdout[i] != INVALID_HANDLE_VALUE)
				CloseHandle((HANDLE)pproc->sv_stdout[i]);
			if ((HANDLE)pproc->sv_stderr[i]
			    && (HANDLE)pproc->sv_stderr[i] != INVALID_HANDLE_VALUE)
				CloseHandle((HANDLE)pproc->sv_stderr[i]);
		}
	}
	if ((HANDLE)pproc->pid)
		CloseHandle((HANDLE)pproc->pid);

	free(pproc);
}


/*
 * Description:
 *	 Create a command line buffer to pass to CreateProcess
 *
 * Returns:  the buffer or NULL for failure
 *	Shell case:  sh_name a:/full/path/to/script argv[1] argv[2] ...
 *  Otherwise:   argv[0] argv[1] argv[2] ...
 *
 * Notes/Dependencies:
 *   CreateProcess does not take an argv, so this command creates a
 *   command line for the executable.
 */

static char *
make_command_line( char *shell_name, char *full_exec_path, char **argv)
{
	int		argc = 0;
	char**		argvi;
	int*		enclose_in_quotes = NULL;
	int*		enclose_in_quotes_i;
	unsigned int	bytes_required = 0;
	char*		command_line;
	char*		command_line_i;
	int  cygwin_mode = 0; /* HAVE_CYGWIN_SHELL */
	int have_sh = 0; /* HAVE_CYGWIN_SHELL */

#ifdef HAVE_CYGWIN_SHELL
	have_sh = (shell_name != NULL || strstr(full_exec_path, "sh.exe"));
	cygwin_mode = 1;
#endif

	if (shell_name && full_exec_path) {
		bytes_required
		  = strlen(shell_name) + 1 + strlen(full_exec_path);
		/*
		 * Skip argv[0] if any, when shell_name is given.
		 */
		if (*argv) argv++;
		/*
		 * Add one for the intervening space.
		 */
		if (*argv) bytes_required++;
	}

	argvi = argv;
	while (*(argvi++)) argc++;

	if (argc) {
		enclose_in_quotes = (int*) calloc(1, argc * sizeof(int));

		if (!enclose_in_quotes) {
			return NULL;
		}
	}

	/* We have to make one pass through each argv[i] to see if we need
	 * to enclose it in ", so we might as well figure out how much
	 * memory we'll need on the same pass.
	 */

	argvi = argv;
	enclose_in_quotes_i = enclose_in_quotes;
	while(*argvi) {
		char* p = *argvi;
		unsigned int backslash_count = 0;

		/*
		 * We have to enclose empty arguments in ".
		 */
		if (!(*p)) *enclose_in_quotes_i = 1;

		while(*p) {
			switch (*p) {
			case '\"':
				/*
				 * We have to insert a backslash for each "
				 * and each \ that precedes the ".
				 */
				bytes_required += (backslash_count + 1);
				backslash_count = 0;
				break;

#if !defined(HAVE_MKS_SHELL) && !defined(HAVE_CYGWIN_SHELL)
			case '\\':
				backslash_count++;
				break;
#endif
	/*
	 * At one time we set *enclose_in_quotes_i for '*' or '?' to suppress
	 * wildcard expansion in programs linked with MSVC's SETARGV.OBJ so
	 * that argv in always equals argv out. This was removed.  Say you have
	 * such a program named glob.exe.  You enter
	 * glob '*'
	 * at the sh command prompt.  Obviously the intent is to make glob do the
	 * wildcarding instead of sh.  If we set *enclose_in_quotes_i for '*' or '?',
	 * then the command line that glob would see would be
	 * glob "*"
	 * and the _setargv in SETARGV.OBJ would _not_ expand the *.
	 */
			case ' ':
			case '\t':
				*enclose_in_quotes_i = 1;
				/* fall through */

			default:
				backslash_count = 0;
				break;
			}

			/*
			 * Add one for each character in argv[i].
			 */
			bytes_required++;

			p++;
		}

		if (*enclose_in_quotes_i) {
			/*
			 * Add one for each enclosing ",
			 * and one for each \ that precedes the
			 * closing ".
			 */
			bytes_required += (backslash_count + 2);
		}

		/*
		 * Add one for the intervening space.
		 */
		if (*(++argvi)) bytes_required++;
		enclose_in_quotes_i++;
	}

	/*
	 * Add one for the terminating NULL.
	 */
	bytes_required++;

	command_line = (char*) malloc(bytes_required);

	if (!command_line) {
		if (enclose_in_quotes) free(enclose_in_quotes);
		return NULL;
	}

	command_line_i = command_line;

	if (shell_name && full_exec_path) {
		while(*shell_name) {
			*(command_line_i++) = *(shell_name++);
		}

		*(command_line_i++) = ' ';

		while(*full_exec_path) {
			*(command_line_i++) = *(full_exec_path++);
		}

		if (*argv) {
			*(command_line_i++) = ' ';
		}
	}

	argvi = argv;
	enclose_in_quotes_i = enclose_in_quotes;

	while(*argvi) {
		char* p = *argvi;
		unsigned int backslash_count = 0;

		if (*enclose_in_quotes_i) {
			*(command_line_i++) = '\"';
		}

		while(*p) {
			if (*p == '\"') {
				if (cygwin_mode && have_sh) { /* HAVE_CYGWIN_SHELL */
					/* instead of a \", cygwin likes "" */
					*(command_line_i++) = '\"';
				} else {

				/*
				 * We have to insert a backslash for the "
				 * and each \ that precedes the ".
				 */
				backslash_count++;

				while(backslash_count) {
					*(command_line_i++) = '\\';
					backslash_count--;
				};
				}
#if !defined(HAVE_MKS_SHELL) && !defined(HAVE_CYGWIN_SHELL)
			} else if (*p == '\\') {
				backslash_count++;
			} else {
				backslash_count = 0;
#endif
			}

			/*
			 * Copy the character.
			 */
			*(command_line_i++) = *(p++);
		}

		if (*enclose_in_quotes_i) {
#if !defined(HAVE_MKS_SHELL) && !defined(HAVE_CYGWIN_SHELL)
			/*
			 * Add one \ for each \ that precedes the
			 * closing ".
			 */
			while(backslash_count--) {
				*(command_line_i++) = '\\';
			};
#endif
			*(command_line_i++) = '\"';
		}

		/*
		 * Append an intervening space.
		 */
		if (*(++argvi)) {
			*(command_line_i++) = ' ';
		}

		enclose_in_quotes_i++;
	}

	/*
	 * Append the terminating NULL.
	 */
	*command_line_i = '\0';

	if (enclose_in_quotes) free(enclose_in_quotes);
	return command_line;
}

/*
 * Description: Given an argv and optional envp, launch the process
 *              using the default stdin, stdout, and stderr handles.
 *              Also, register process so that process_wait_for_any_private()
 *		can be used via process_file_io(NULL) or
 *		process_wait_for_any().
 *
 * Returns:
 *
 * Notes/Dependencies:
 */
HANDLE
process_easy(
	char **argv,
	char **envp)
{
  HANDLE hIn = INVALID_HANDLE_VALUE;
  HANDLE hOut = INVALID_HANDLE_VALUE;
  HANDLE hErr = INVALID_HANDLE_VALUE;
  HANDLE hProcess, tmpIn, tmpOut, tmpErr;
  DWORD e;

  if (proc_index >= MAXIMUM_WAIT_OBJECTS) {
	DB (DB_JOBS, ("process_easy: All process slots used up\n"));
	return INVALID_HANDLE_VALUE;
  }
  /* Standard handles returned by GetStdHandle can be NULL or
     INVALID_HANDLE_VALUE if the parent process closed them.  If that
     happens, we open the null device and pass its handle to
     CreateProcess as the corresponding handle to inherit.  */
  tmpIn = GetStdHandle(STD_INPUT_HANDLE);
  if (DuplicateHandle(GetCurrentProcess(),
		      tmpIn,
		      GetCurrentProcess(),
		      &hIn,
		      0,
		      TRUE,
		      DUPLICATE_SAME_ACCESS) == FALSE) {
    if ((e = GetLastError()) == ERROR_INVALID_HANDLE) {
      tmpIn = CreateFile("NUL", GENERIC_READ,
			 FILE_SHARE_READ | FILE_SHARE_WRITE, NULL,
			 OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
      if (tmpIn != INVALID_HANDLE_VALUE
	  && DuplicateHandle(GetCurrentProcess(),
			     tmpIn,
			     GetCurrentProcess(),
			     &hIn,
			     0,
			     TRUE,
			     DUPLICATE_SAME_ACCESS) == FALSE)
	CloseHandle(tmpIn);
    }
    if (hIn == INVALID_HANDLE_VALUE) {
      fprintf(stderr, "process_easy: DuplicateHandle(In) failed (e=%ld)\n", e);
      return INVALID_HANDLE_VALUE;
    }
  }
  tmpOut = GetStdHandle (STD_OUTPUT_HANDLE);
  if (DuplicateHandle(GetCurrentProcess(),
		      tmpOut,
		      GetCurrentProcess(),
		      &hOut,
		      0,
		      TRUE,
		      DUPLICATE_SAME_ACCESS) == FALSE) {
    if ((e = GetLastError()) == ERROR_INVALID_HANDLE) {
      tmpOut = CreateFile("NUL", GENERIC_WRITE,
			  FILE_SHARE_READ | FILE_SHARE_WRITE, NULL,
			  OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
      if (tmpOut != INVALID_HANDLE_VALUE
	  && DuplicateHandle(GetCurrentProcess(),
			     tmpOut,
			     GetCurrentProcess(),
			     &hOut,
			     0,
			     TRUE,
			     DUPLICATE_SAME_ACCESS) == FALSE)
	CloseHandle(tmpOut);
    }
    if (hOut == INVALID_HANDLE_VALUE) {
      fprintf(stderr, "process_easy: DuplicateHandle(Out) failed (e=%ld)\n", e);
      return INVALID_HANDLE_VALUE;
    }
  }
  tmpErr = GetStdHandle(STD_ERROR_HANDLE);
  if (DuplicateHandle(GetCurrentProcess(),
		      tmpErr,
		      GetCurrentProcess(),
		      &hErr,
		      0,
		      TRUE,
		      DUPLICATE_SAME_ACCESS) == FALSE) {
    if ((e = GetLastError()) == ERROR_INVALID_HANDLE) {
      tmpErr = CreateFile("NUL", GENERIC_WRITE,
			  FILE_SHARE_READ | FILE_SHARE_WRITE, NULL,
			  OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
      if (tmpErr != INVALID_HANDLE_VALUE
	  && DuplicateHandle(GetCurrentProcess(),
			     tmpErr,
			     GetCurrentProcess(),
			     &hErr,
			     0,
			     TRUE,
			     DUPLICATE_SAME_ACCESS) == FALSE)
	CloseHandle(tmpErr);
    }
    if (hErr == INVALID_HANDLE_VALUE) {
      fprintf(stderr, "process_easy: DuplicateHandle(Err) failed (e=%ld)\n", e);
      return INVALID_HANDLE_VALUE;
    }
  }

  hProcess = process_init_fd(hIn, hOut, hErr);

  if (process_begin(hProcess, argv, envp, argv[0], NULL)) {
    fake_exits_pending++;
    /* process_begin() failed: make a note of that.  */
    if (!((sub_process*) hProcess)->last_err)
      ((sub_process*) hProcess)->last_err = -1;
    ((sub_process*) hProcess)->exit_code = process_last_err(hProcess);

    /* close up unused handles */
    if (hIn != INVALID_HANDLE_VALUE)
      CloseHandle(hIn);
    if (hOut != INVALID_HANDLE_VALUE)
      CloseHandle(hOut);
    if (hErr != INVALID_HANDLE_VALUE)
      CloseHandle(hErr);
  }

  process_register(hProcess);

  return hProcess;
}