pipechan.cxx

安装 H323需要的pwlib库

/*
 * pipechan.cxx
 *
 * Sub-process commuicating with pip I/O channel implementation
 *
 * Portable Windows Library
 *
 * Copyright (c) 1993-1998 Equivalence Pty. Ltd.
 *
 * The contents of this file are subject to the Mozilla Public License
 * Version 1.0 (the "License"); you may not use this file except in
 * compliance with the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS"
 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
 * the License for the specific language governing rights and limitations
 * under the License.
 *
 * The Original Code is Portable Windows Library.
 *
 * The Initial Developer of the Original Code is Equivalence Pty. Ltd.
 *
 * Portions are Copyright (C) 1993 Free Software Foundation, Inc.
 * All Rights Reserved.
 *
 * Contributor(s): ______________________________________.
 *
 * $Log: pipechan.cxx,v $
 * Revision 1.42.8.1  2005/02/04 05:19:12  csoutheren
 * Backported patches from Atlas-devel
 *
 * Revision 1.43  2004/12/15 00:39:01  csoutheren
 * Fixed problem with passing arguments to PPipeChannel, thanks to Derek Smithies
 *
 * Revision 1.42  2003/04/22 23:43:51  craigs
 * MacOSX changes as per Hugo Santos
 *
 * Revision 1.41  2003/01/09 08:21:47  robertj
 * Fixed possibly handle leak if fork() fails.
 * Also added belt and braces checks for making sure no handle can leak in
 *   other unknown logic. Plus do handle high water mark logging.
 *
 * Revision 1.40  2003/01/08 01:33:52  craigs
 * Fixed problem with not checking errno on return from waitpid
 *
 * Revision 1.39  2003/01/08 01:29:22  craigs
 * More changes for return code to waitpid
 *
 * Revision 1.38  2002/12/18 01:12:09  craigs
 * Remove erroneous WUNTRACED and added support for EINTR from waitpid
 *
 * Revision 1.37  2002/12/05 05:11:16  craigs
 * Fixed IsRunning and WaitForTermination to provide the correct return
 * codes from subprograms
 *
 * Revision 1.36  2002/12/02 03:57:18  robertj
 * More RTEMS support patches, thank you Vladimir Nesic.
 *
 * Revision 1.35  2002/11/22 10:14:07  robertj
 * QNX port, thanks Xiaodan Tang
 *
 * Revision 1.34  2002/10/17 13:44:27  robertj
 * Port to RTEMS, thanks Vladimir Nesic.
 *
 * Revision 1.33  2002/10/10 04:43:44  robertj
 * VxWorks port, thanks Martijn Roest
 *
 * Revision 1.32  2002/07/31 07:30:11  craigs
 * WaitForTermination now returns exit code of program, as required
 *
 * Revision 1.31  2001/10/11 02:20:54  robertj
 * Added IRIX support (no audio/video), thanks Andre Schulze.
 *
 * Revision 1.30  2001/08/16 11:58:22  rogerh
 * Add more Mac OS X changes from John Woods <[e-mail]>
 *
 * Revision 1.29  2001/08/12 06:32:04  rogerh
 * Add Mac OS Carbon changes from John Woods <[e-mail]>
 *
 * Revision 1.28  2001/06/30 06:59:07  yurik
 * Jac Goudsmit from Be submit these changes 6/28. Implemented by Yuri Kiryanov
 *
 * Revision 1.27  2000/06/21 01:01:22  robertj
 * AIX port, thanks Wolfgang Platzer ([e-mail]).
 *
 * Revision 1.26  2000/04/09 18:19:23  rogerh
 * Add my changes for NetBSD support.
 *
 * Revision 1.25  2000/04/06 12:11:32  rogerh
 * MacOS X support submitted by Kevin Packard
 *
 * Revision 1.24  2000/03/08 12:17:09  rogerh
 * Add OpenBSD support
 *
 * Revision 1.23  1999/06/28 09:28:02  robertj
 * Portability issues, especially n BeOS (thanks Yuri!)
 *
 * Revision 1.22  1999/02/22 13:26:54  robertj
 * BeOS port changes.
 *
 * Revision 1.21  1998/11/30 21:51:46  robertj
 * New directory structure.
 *
 * Revision 1.20  1998/11/24 10:25:19  robertj
 * Fixed environment variable on FreeBSD
 *
 * Revision 1.19  1998/11/24 09:39:11  robertj
 * FreeBSD port.
 *
 * Revision 1.18  1998/11/06 01:06:05  robertj
 * Solaris environment variable name.
 *
 * Revision 1.17  1998/11/05 09:42:01  robertj
 * Fixed bug in direct stdout mode opening redirected stdout.
 * Solaris support, missing environ declaration.
 * Added assert for unsupported timeout in WaitForTermination() under solaris.
 *
 * Revision 1.16  1998/11/02 11:11:19  robertj
 * Added pipe output to stdout/stderr.
 *
 * Revision 1.15  1998/11/02 10:30:40  robertj
 * GNU v6 compatibility.
 *
 * Revision 1.14  1998/11/02 10:07:34  robertj
 * Added ReadStandardError implementation
 *
 * Revision 1.13  1998/10/30 13:02:50  robertj
 * New pipe channel enhancements.
 *
 * Revision 1.12  1998/10/26 11:09:56  robertj
 * added separation of stdout and stderr.
 *
 * Revision 1.11  1998/09/24 04:12:14  robertj
 * Added open software license.
 *
 */

#pragma implementation "pipechan.h"

#include <ptlib.h>
#include <ptlib/pipechan.h>

#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <fcntl.h>
#include <signal.h>

#if defined(P_LINUX) || defined(P_SOLARIS)
#include <termio.h>
#endif

#if defined(P_MACOSX)
#include <crt_externs.h>
#endif

#include "../common/pipechan.cxx"


int PX_NewHandle(const char *, int);


////////////////////////////////////////////////////////////////
//
//  PPipeChannel
//

PPipeChannel::PPipeChannel()
{
  toChildPipe[0] = toChildPipe[1] = -1;
  fromChildPipe[0] = fromChildPipe[1] = -1;
  stderrChildPipe[0] = stderrChildPipe[1] = -1;
}


BOOL PPipeChannel::PlatformOpen(const PString & subProgram,
                                const PStringArray & argumentList,
                                OpenMode mode,
                                BOOL searchPath,
                                BOOL stderrSeparate,
                                const PStringToString * environment)
{
#if defined(P_VXWORKS) || defined(P_RTEMS)
  PAssertAlways("PPipeChannel::PlatformOpen");
  return FALSE;
#else
  subProgName = subProgram;

  // setup the pipe to the child
  if (mode == ReadOnly)
    toChildPipe[0] = toChildPipe[1] = -1;
  else {
    PAssert(pipe(toChildPipe) == 0, POperatingSystemError);
    PX_NewHandle("PPipeChannel toChildPipe", PMAX(toChildPipe[0], toChildPipe[1]));
  }
 
  // setup the pipe from the child
  if (mode == WriteOnly || mode == ReadWriteStd)
    fromChildPipe[0] = fromChildPipe[1] = -1;
  else {
    PAssert(pipe(fromChildPipe) == 0, POperatingSystemError);
    PX_NewHandle("PPipeChannel fromChildPipe", PMAX(fromChildPipe[0], fromChildPipe[1]));
  }

  if (stderrSeparate)
    PAssert(pipe(stderrChildPipe) == 0, POperatingSystemError);
  else {
    stderrChildPipe[0] = stderrChildPipe[1] = -1;
    PX_NewHandle("PPipeChannel stderrChildPipe", PMAX(stderrChildPipe[0], stderrChildPipe[1]));
  }

  // fork to allow us to execute the child
#if defined(__BEOS__) || defined(P_IRIX)
  childPid = fork();
#else
  childPid = vfork();
#endif
  if (childPid < 0)
    return FALSE;

  if (childPid > 0) {
    // setup the pipe to the child
    if (toChildPipe[0] != -1) {
      ::close(toChildPipe[0]);
      toChildPipe[0] = -1;
    }

    if (fromChildPipe[1] != -1) {
      ::close(fromChildPipe[1]);
      fromChildPipe[1] = -1;
    }
 
    if (stderrChildPipe[1] != -1) {
      ::close(stderrChildPipe[1]);
      stderrChildPipe[1] = -1;
    }
 
    os_handle = 0;
    return TRUE;
  }

  // the following code is in the child process

  // if we need to write to the child, make sure the child's stdin
  // is redirected
  if (toChildPipe[0] != -1) {
    ::close(STDIN_FILENO);
    ::dup(toChildPipe[0]);
    ::close(toChildPipe[0]);
    ::close(toChildPipe[1]);  
  } else {
    int fd = open("/dev/null", O_RDONLY);
    PAssertOS(fd >= 0);
    ::close(STDIN_FILENO);
    ::dup(fd);
    ::close(fd);
  }

  // if we need to read from the child, make sure the child's stdout
  // and stderr is redirected
  if (fromChildPipe[1] != -1) {
    ::close(STDOUT_FILENO);
    ::dup(fromChildPipe[1]);
    ::close(STDERR_FILENO);
    if (!stderrSeparate)
      ::dup(fromChildPipe[1]);
    ::close(fromChildPipe[1]);
    ::close(fromChildPipe[0]); 
  } else if (mode != ReadWriteStd) {
    int fd = ::open("/dev/null", O_WRONLY);
    PAssertOS(fd >= 0);
    ::close(STDOUT_FILENO);
    ::dup(fd);
    ::close(STDERR_FILENO);
    if (!stderrSeparate)
      ::dup(fd);
    ::close(fd);
  }

  if (stderrSeparate) {
    ::dup(stderrChildPipe[1]);
    ::close(stderrChildPipe[1]);
    ::close(stderrChildPipe[0]); 
  }

  // set the SIGINT and SIGQUIT to ignore so the child process doesn't
  // inherit them from the parent
  signal(SIGINT,  SIG_IGN);
  signal(SIGQUIT, SIG_IGN);