pipechan.h

开源代码的pwlib的1.10.0版本,使用openh323的1.18.0版本毕备

/*
 * pipechan.h
 *
 * Sub-process with communications using pipe I/O channel class.
 *
 * 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.h,v $
 * Revision 1.23  2005/11/25 03:43:47  csoutheren
 * Fixed function argument comments to be compatible with Doxygen
 *
 * Revision 1.22  2003/09/17 05:41:59  csoutheren
 * Removed recursive includes
 *
 * Revision 1.21  2003/09/17 01:18:02  csoutheren
 * Removed recursive include file system and removed all references
 * to deprecated coooperative threading support
 *
 * Revision 1.20  2002/09/16 01:08:59  robertj
 * Added #define so can select if #pragma interface/implementation is used on
 *   platform basis (eg MacOS) rather than compiler, thanks Robert Monaghan.
 *
 * Revision 1.19  2001/05/22 12:49:32  robertj
 * Did some seriously wierd rewrite of platform headers to eliminate the
 *   stupid GNU compiler warning about braces not matching.
 *
 * Revision 1.18  1999/03/09 02:59:50  robertj
 * Changed comments to doc++ compatible documentation.
 *
 * Revision 1.17  1999/02/16 08:11:09  robertj
 * MSVC 6.0 compatibility changes.
 *
 * Revision 1.16  1998/11/02 10:06:39  robertj
 * Added capability of pip output to go to stdout/stderr.
 *
 * Revision 1.15  1998/10/30 10:42:29  robertj
 * Better function arrangement for multi platforming.
 *
 * Revision 1.14  1998/10/29 11:29:17  robertj
 * Added ability to set environment in sub-process.
 *
 * Revision 1.13  1998/10/26 09:11:05  robertj
 * Added ability to separate out stdout from stderr on pipe channels.
 *
 * Revision 1.12  1998/09/23 06:21:08  robertj
 * Added open source copyright license.
 *
 * Revision 1.11  1997/01/03 05:25:05  robertj
 * Added Wait and Kill functions.
 *
 * Revision 1.10  1996/03/31 08:50:51  robertj
 * Changed string list to array.
 * Added function to idicate if sub-process is running.
 *
 * Revision 1.9  1995/07/31 12:15:45  robertj
 * Removed PContainer from PChannel ancestor.
 *
 * Revision 1.8  1995/06/17 11:12:53  robertj
 * Documentation update.
 *
 * Revision 1.7  1995/03/14 12:42:02  robertj
 * Updated documentation to use HTML codes.
 *
 * Revision 1.6  1995/01/09  12:39:01  robertj
 * Documentation.
 *
 * Revision 1.5  1994/10/23  04:50:55  robertj
 * Further refinement of semantics after implementation.
 *
 * Revision 1.4  1994/09/25  10:43:19  robertj
 * Added more implementation.
 *
 * Revision 1.3  1994/08/23  11:32:52  robertj
 * Oops
 *
 * Revision 1.2  1994/08/22  00:46:48  robertj
 * Added pragma fro GNU C++ compiler.
 *
 * Revision 1.1  1994/04/20  12:17:44  robertj
 * Initial revision
 *
 */

#ifndef _PPIPECHANNEL
#define _PPIPECHANNEL

#ifdef P_USE_PRAGMA
#pragma interface
#endif


/**A channel that uses a operating system pipe between the current process and
   a sub-process. On platforms that support {\it multi-processing}, the
   sub-program is executed concurrently with the calling process.
   
   Where full multi-processing is not supported then the sub-program is run
   with its input supplied from, or output captured to, a disk file. The
   current process is then suspended during the execution of the sub-program.
   In the latter case the semantics of the #Execute()# and #Close()#
   functions change from the usual for channels.

   Note that for platforms that do not support multi-processing, the current
   process is suspended until the sub-program terminates. The input and output
   of the sub-program is transferred via a temporary file. The exact moment of
   execution of the sub-program depends on the mode. If mode is
   #ReadOnly# then it is executed immediately and its output
   captured. In #WriteOnly# mode the sub-program is run when the
   #Close()# function is called, or when the pipe channel is destroyed.
   In #ReadWrite# mode the sub-program is run when the
   #Execute()# function is called indicating that the output from the
   current process to the sub-program has completed and input is now desired.
   
   The #CanReadAndWrite()# function effectively determines whether full
   multi-processing is supported by the platform. Note that this is different
   to whether {\it multi-threading} is supported.
 */
class PPipeChannel : public PChannel
{
  PCLASSINFO(PPipeChannel, PChannel);

  public:
  /**@name Construction */
  //@{
    /// Channel mode for the pipe to the sub-process.
    enum OpenMode {
      /// Pipe is only from the sub-process to the current process.
      ReadOnly,   
      /// Pipe is only from the current process to the sub-process.
      WriteOnly,  
      /// Pipe is bidirectional between current and sub-processes.
      ReadWrite,  
      /**Pipe is bidirectional between current and sub-processes but the write
         side goes to stdout and stderr */
      ReadWriteStd
    };

    /**Create a new pipe channel.
     */
    PPipeChannel();
    /**Create a new pipe channel.
       This executes the subProgram and transfers data from its stdin/stdout/stderr.
       
       See the #Open()# function for details of various parameters.
     */
    PPipeChannel(
      const PString & subProgram,  ///< Sub program name or command line.
      OpenMode mode = ReadWrite,   ///< Mode for the pipe channel.
      BOOL searchPath = TRUE,      ///< Flag for system PATH to be searched.
      BOOL stderrSeparate = FALSE  ///< Standard error is on separate pipe
    );
    /**Create a new pipe channel.
       This executes the subProgram and transfers data from its stdin/stdout/stderr.
       
       See the #Open()# function for details of various parameters.
     */
    PPipeChannel(
      const PString & subProgram,  ///< Sub program name or command line.
      const PStringArray & argumentList, ///< Array of arguments to sub-program.
      OpenMode mode = ReadWrite,   ///< Mode for the pipe channel.
      BOOL searchPath = TRUE,      ///< Flag for system PATH to be searched.
      BOOL stderrSeparate = FALSE  ///< Standard error is on separate pipe
    );
    /**Create a new pipe channel.
       This executes the subProgram and transfers data from its stdin/stdout/stderr.
       
       See the #Open()# function for details of various parameters.
     */
    PPipeChannel(
      const PString & subProgram,  ///< Sub program name or command line.
      const PStringToString & environment, ///< Array of arguments to sub-program.
      OpenMode mode = ReadWrite,   ///< Mode for the pipe channel.
      BOOL searchPath = TRUE,      ///< Flag for system PATH to be searched.
      BOOL stderrSeparate = FALSE  ///< Standard error is on separate pipe
    );
    /**Create a new pipe channel.
       This executes the subProgram and transfers data from its stdin/stdout/stderr.
       
       See the #Open()# function for details of various parameters.
     */
    PPipeChannel(
      const PString & subProgram,  ///< Sub program name or command line.
      const PStringArray & argumentList, ///< Array of arguments to sub-program.
      const PStringToString & environment, ///< Array of arguments to sub-program.
      OpenMode mode = ReadWrite,   ///< Mode for the pipe channel.
      BOOL searchPath = TRUE,      ///< Flag for system PATH to be searched.
      BOOL stderrSeparate = FALSE  ///< Standard error is on separate pipe
    );

    /// Close the pipe channel, killing the sub-process.
    ~PPipeChannel();
  //@}

  /**@name Overrides from class PObject */
  //@{
    /**Determine if the two objects refer to the same pipe channel. This
       actually compares the sub-program names that are passed into the
       constructor.

       @return
       Comparison value of the sub-program strings.
     */
    Comparison Compare(
      const PObject & obj   ///< Another pipe channel to compare against.
    ) const;
  //@}


  /**@name Overrides from class PChannel */
  //@{
    /**Get the name of the channel.
    
       @return
       string for the sub-program that is run.
     */
    virtual PString GetName() const;

    /**Low level read from the channel. This function may block until the
       requested number of characters were read or the read timeout was