// -*- c++ -*-
/* $Id: spawn.ccg,v 1.3 2002/10/23 01:48:03 daniel Exp $ */

/* Copyright (C) 2002 The gtkmm Development Team
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the Free
 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <glib/gspawn.h>
#include <glibmm/exceptionhandler.h>
#include <glibmm/utility.h>


namespace
{

/* Helper callback to invoke the actual sigc++ slot.
 * We don't need to worry about (un)referencing, since the
 * child process gets its own copy of the parent's memory anyway.
 */
void child_setup_callback(void* user_data)
{
  try
  {
    SigC::Slot0<void> slot (static_cast<SigC::SlotNode*>(user_data));
    slot();
  }
  catch(...)
  {
    Glib::exception_handlers_invoke();
  }
}

void copy_output_buf(std::string* dest, const char* buf)
{
  if(dest)
  {
    if(buf)
      *dest = buf;
    else
      dest->erase();
  }
}

}


namespace Glib
{

/**** process spawning functions *******************************************/

void spawn_async_with_pipes(const std::string& working_directory,
                            const Glib::ArrayHandle<std::string>& argv,
                            const Glib::ArrayHandle<std::string>& envp,
                            SpawnFlags flags,
                            const SigC::Slot0<void>& child_setup,
                            int* child_pid,
                            int* standard_input,
                            int* standard_output,
                            int* standard_error)
{
  const bool setup_slot = !child_setup.empty();
  GError* error = 0;

  g_spawn_async_with_pipes(
      working_directory.c_str(),
      const_cast<char**>(argv.data()),
      const_cast<char**>(envp.data()),
      static_cast<GSpawnFlags>(unsigned(flags)),
      (setup_slot) ? &child_setup_callback : 0,
      (setup_slot) ? child_setup.impl()    : 0,
      child_pid,
      standard_input, standard_output, standard_error,
      &error);

  if(error)
    Glib::Error::throw_exception(error);
}

void spawn_async_with_pipes(const std::string& working_directory,
                            const Glib::ArrayHandle<std::string>& argv,
                            SpawnFlags flags,
                            const SigC::Slot0<void>& child_setup,
                            int* child_pid,
                            int* standard_input,
                            int* standard_output,
                            int* standard_error)
{
  const bool setup_slot = !child_setup.empty();
  GError* error = 0;

  g_spawn_async_with_pipes(
      working_directory.c_str(),
      const_cast<char**>(argv.data()), 0,
      static_cast<GSpawnFlags>(unsigned(flags)),
      (setup_slot) ? &child_setup_callback : 0,
      (setup_slot) ? child_setup.impl()    : 0,
      child_pid,
      standard_input, standard_output, standard_error,
      &error);

  if(error)
    Glib::Error::throw_exception(error);
}

void spawn_async(const std::string& working_directory,
                 const Glib::ArrayHandle<std::string>& argv,
                 const Glib::ArrayHandle<std::string>& envp,
                 SpawnFlags flags,
                 const SigC::Slot0<void>& child_setup,
                 int* child_pid)
{
  const bool setup_slot = !child_setup.empty();
  GError* error = 0;

  g_spawn_async(
      working_directory.c_str(),
      const_cast<char**>(argv.data()),
      const_cast<char**>(envp.data()),
      static_cast<GSpawnFlags>(unsigned(flags)),
      (setup_slot) ? &child_setup_callback : 0,
      (setup_slot) ? child_setup.impl()    : 0,
      child_pid,
      &error);

  if(error)
    Glib::Error::throw_exception(error);
}

void spawn_async(const std::string& working_directory,
                 const Glib::ArrayHandle<std::string>& argv,
                 SpawnFlags flags,
                 const SigC::Slot0<void>& child_setup,
                 int* child_pid)
{
  const bool setup_slot = !child_setup.empty();
  GError* error = 0;

  g_spawn_async(
      working_directory.c_str(),
      const_cast<char**>(argv.data()), 0,
      static_cast<GSpawnFlags>(unsigned(flags)),
      (setup_slot) ? &child_setup_callback : 0,
      (setup_slot) ? child_setup.impl()    : 0,
      child_pid,
      &error);

  if(error)
    Glib::Error::throw_exception(error);
}

void spawn_sync(const std::string& working_directory,
                const Glib::ArrayHandle<std::string>& argv,
                const Glib::ArrayHandle<std::string>& envp,
                SpawnFlags flags,
                const SigC::Slot0<void>& child_setup,
                std::string* standard_output,
                std::string* standard_error,
                int* exit_status)
{
  const bool setup_slot = !child_setup.empty();

  Glib::ScopedPtr<char> buf_standard_output;
  Glib::ScopedPtr<char> buf_standard_error;
  GError* error = 0;

  g_spawn_sync(
      working_directory.c_str(),
      const_cast<char**>(argv.data()),
      const_cast<char**>(envp.data()),
      static_cast<GSpawnFlags>(unsigned(flags)),
      (setup_slot) ? &child_setup_callback : 0,
      (setup_slot) ? child_setup.impl()    : 0,
      (standard_output) ? buf_standard_output.addr() : 0,
      (standard_error)  ? buf_standard_error.addr()  : 0,
      exit_status,
      &error);

  if(error)
    Glib::Error::throw_exception(error);

  copy_output_buf(standard_output, buf_standard_output.get());
  copy_output_buf(standard_error, buf_standard_error.get());
}

void spawn_sync(const std::string& working_directory,
                const Glib::ArrayHandle<std::string>& argv,
                SpawnFlags flags,
                const SigC::Slot0<void>& child_setup,
                std::string* standard_output,
                std::string* standard_error,
                int* exit_status)
{
  const bool setup_slot = !child_setup.empty();

  Glib::ScopedPtr<char> buf_standard_output;
  Glib::ScopedPtr<char> buf_standard_error;
  GError* error = 0;

  g_spawn_sync(
      working_directory.c_str(),
      const_cast<char**>(argv.data()), 0,
      static_cast<GSpawnFlags>(unsigned(flags)),
      (setup_slot) ? &child_setup_callback : 0,
      (setup_slot) ? child_setup.impl()    : 0,
      (standard_output) ? buf_standard_output.addr() : 0,
      (standard_error)  ? buf_standard_error.addr()  : 0,
      exit_status,
      &error);

  if(error)
    Glib::Error::throw_exception(error);

  copy_output_buf(standard_output, buf_standard_output.get());
  copy_output_buf(standard_error, buf_standard_error.get());
}

void spawn_command_line_async(const std::string& command_line)
{
  GError* error = 0;
  g_spawn_command_line_async(command_line.c_str(), &error);

  if(error)
    Glib::Error::throw_exception(error);
}

void spawn_command_line_sync(const std::string& command_line,
                             std::string* standard_output,
                             std::string* standard_error,
                             int* exit_status)
{
  Glib::ScopedPtr<char> buf_standard_output;
  Glib::ScopedPtr<char> buf_standard_error;
  GError* error = 0;

  g_spawn_command_line_sync(
      command_line.c_str(),
      (standard_output) ? buf_standard_output.addr() : 0,
      (standard_error)  ? buf_standard_error.addr()  : 0,
      exit_status,
      &error);

  if(error)
    Glib::Error::throw_exception(error);

  copy_output_buf(standard_output, buf_standard_output.get());
  copy_output_buf(standard_error, buf_standard_error.get());
}

} // namespace Glib