gimp/app/plug-in/gimpplugin.c

/* The GIMP -- an image manipulation program
 * Copyright (C) 1995 Spencer Kimball and Peter Mattis
 *
 * This program 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 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#include "config.h"

#include <signal.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#ifdef HAVE_SYS_WAIT_H
#include <sys/wait.h>
#endif

#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#endif

#ifdef HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif

#include <gtk/gtk.h>

#if defined(G_OS_WIN32) || defined(G_WITH_CYGWIN)

#define STRICT
#include <windows.h>
#include <process.h>

#ifdef G_OS_WIN32
#include <fcntl.h>
#include <io.h>
#endif

#ifdef G_WITH_CYGWIN
#define O_TEXT		0x0100	/* text file */
#define _O_TEXT		0x0100	/* text file */
#define O_BINARY	0x0200	/* binary file */
#define _O_BINARY	0x0200	/* binary file */
#endif

#endif /* G_OS_WIN32 || G_WITH_CYGWIN */

#ifdef __EMX__
#include <fcntl.h>
#include <process.h>
#define _O_BINARY O_BINARY
#define _P_NOWAIT P_NOWAIT
#endif

#ifdef HAVE_IPC_H
#include <sys/ipc.h>
#endif

#ifdef HAVE_SHM_H
#include <sys/shm.h>
#endif

#include "libgimpbase/gimpbase.h"
#include "libgimpbase/gimpprotocol.h"
#include "libgimpbase/gimpwire.h"

#include "plug-in-types.h"

#include "base/tile.h"
#include "base/tile-manager.h"

#include "core/gimp.h"
#include "core/gimpenvirontable.h"

#include "gui/brush-select.h"
#include "gui/gradient-select.h"
#include "gui/palette-select.h"
#include "gui/pattern-select.h"

#include "plug-in.h"
#include "plug-ins.h"
#include "plug-in-def.h"
#include "plug-in-message.h"
#include "plug-in-params.h"
#include "plug-in-proc.h"
#include "plug-in-progress.h"
#include "plug-in-shm.h"

#include "libgimp/gimpintl.h"


/*  local funcion prototypes  */

static gboolean   plug_in_write         (GIOChannel   *channel,
                                         guint8       *buf,
                                         gulong        count,
                                         gpointer      user_data);
static gboolean   plug_in_flush         (GIOChannel   *channel,
                                         gpointer      user_data);

static gboolean   plug_in_recv_message  (GIOChannel   *channel,
                                         GIOCondition  cond,
                                         gpointer      data);

static void       plug_in_prep_for_exec (gpointer      data);


/*  global variables  */

PlugIn *current_plug_in = NULL;


/*  private variables  */

static GSList *open_plug_ins = NULL;
static GSList *plug_in_stack = NULL;


void
plug_in_init (Gimp *gimp)
{
  g_return_if_fail (GIMP_IS_GIMP (gimp));

  /* initialize the gimp protocol library and set the read and
   *  write handlers.
   */
  gp_init ();
  wire_set_writer (plug_in_write);
  wire_set_flusher (plug_in_flush);

  /* allocate a piece of shared memory for use in transporting tiles
   *  to plug-ins. if we can't allocate a piece of shared memory then
   *  we'll fall back on sending the data over the pipe.
   */
  if (gimp->use_shm)
    plug_in_shm_init (gimp);
}

void
plug_in_exit (Gimp *gimp)
{
  GSList *list;

  g_return_if_fail (GIMP_IS_GIMP (gimp));

  if (gimp->use_shm)
    plug_in_shm_exit (gimp);

  list = open_plug_ins;
  while (list)
    {
      PlugIn *plug_in;

      plug_in = (PlugIn *) list->data;

      list = list->next;

      if (plug_in->open)
        plug_in_close (plug_in, TRUE);

      plug_in_unref (plug_in);
    }
}

void
plug_in_call_query (Gimp      *gimp,
                    PlugInDef *plug_in_def)
{
  PlugIn *plug_in;

  g_return_if_fail (GIMP_IS_GIMP (gimp));
  g_return_if_fail (plug_in_def != NULL);

  plug_in = plug_in_new (gimp, plug_in_def->prog);

  if (plug_in)
    {
      plug_in->query       = TRUE;
      plug_in->synchronous = TRUE;
      plug_in->plug_in_def = plug_in_def;

      if (plug_in_open (plug_in))
	{
	  while (plug_in->open)
	    {
              WireMessage msg;

	      if (! wire_read_msg (plug_in->my_read, &msg, plug_in))
                {
                  plug_in_close (plug_in, TRUE);
                }
	      else 
		{
		  plug_in_handle_message (plug_in, &msg);
		  wire_destroy (&msg);
		}
	    }
	}

      plug_in_unref (plug_in);
    }
}

void
plug_in_call_init (Gimp      *gimp,
                   PlugInDef *plug_in_def)
{
  PlugIn *plug_in;

  g_return_if_fail (GIMP_IS_GIMP (gimp));
  g_return_if_fail (plug_in_def != NULL);

  plug_in = plug_in_new (gimp, plug_in_def->prog);

  if (plug_in)
    {
      plug_in->init        = TRUE;
      plug_in->synchronous = TRUE;
      plug_in->plug_in_def = plug_in_def;

      if (plug_in_open (plug_in))
	{
	  while (plug_in->open)
	    {
              WireMessage msg;

	      if (! wire_read_msg (plug_in->my_read, &msg, plug_in))
                {
                  plug_in_close (plug_in, TRUE);
                }
	      else 
		{
		  plug_in_handle_message (plug_in, &msg);
		  wire_destroy (&msg);
		}
	    }
	}

      plug_in_unref (plug_in);
    }
}

PlugIn *
plug_in_new (Gimp  *gimp,
             gchar *name)
{
  PlugIn *plug_in;

  g_return_val_if_fail (GIMP_IS_GIMP (gimp), NULL);
  g_return_val_if_fail (name != NULL, NULL);
  g_return_val_if_fail (g_path_is_absolute (name), NULL);

  plug_in = g_new0 (PlugIn, 1);

  plug_in->gimp               = gimp;

  plug_in->ref_count          = 1;

  plug_in->open               = FALSE;
  plug_in->query              = FALSE;
  plug_in->init               = FALSE;
  plug_in->synchronous        = FALSE;
  plug_in->recurse            = FALSE;
  plug_in->in_temp_proc       = FALSE;
  plug_in->starting_ext       = FALSE;
  plug_in->pid                = 0;

  plug_in->args[0]            = g_strdup (name);
  plug_in->args[1]            = g_strdup ("-gimp");
  plug_in->args[2]            = NULL;
  plug_in->args[3]            = NULL;
  plug_in->args[4]            = NULL;
  plug_in->args[5]            = NULL;
  plug_in->args[6]            = NULL;

  plug_in->my_read            = NULL;
  plug_in->my_write           = NULL;
  plug_in->his_read           = NULL;
  plug_in->his_write          = NULL;

  plug_in->input_id           = 0;
  plug_in->write_buffer_index = 0;

  plug_in->temp_proc_defs     = NULL;

  plug_in->main_loops         = NULL;
  plug_in->return_vals        = NULL;
  plug_in->n_return_vals      = 0;

  plug_in->progress           = NULL;
  plug_in->plug_in_def        = NULL;

  return plug_in;
}

void
plug_in_ref (PlugIn *plug_in)
{
  g_return_if_fail (plug_in != NULL);

  plug_in->ref_count++;
}

void
plug_in_unref (PlugIn *plug_in)
{
  g_return_if_fail (plug_in != NULL);

  plug_in->ref_count--;

  if (plug_in->ref_count < 1)
    {
      if (plug_in->open)
        plug_in_close (plug_in, TRUE);

      if (plug_in->args[0])
        g_free (plug_in->args[0]);
      if (plug_in->args[1])
        g_free (plug_in->args[1]);
      if (plug_in->args[2])
        g_free (plug_in->args[2]);
      if (plug_in->args[3])
        g_free (plug_in->args[3]);
      if (plug_in->args[4])
        g_free (plug_in->args[4]);
      if (plug_in->args[5])
        g_free (plug_in->args[5]);

      if (plug_in->progress)
        plug_in_progress_end (plug_in);

      g_free (plug_in);
    }
}

static void
plug_in_prep_for_exec (gpointer data)
{
#if !defined(G_OS_WIN32) && !defined (G_WITH_CYGWIN) && !defined(__EMX__)
  PlugIn *plug_in = data;

  g_io_channel_unref (plug_in->my_read);
  plug_in->my_read  = NULL;

  g_io_channel_unref (plug_in->my_write);
  plug_in->my_write  = NULL;
#endif
}

gboolean
plug_in_open (PlugIn *plug_in)
{
  gint    my_read[2];
  gint    my_write[2];
  gchar **envp;
  GError *error = NULL;

  g_return_val_if_fail (plug_in != NULL, FALSE);

  /* Open two pipes. (Bidirectional communication).
   */
  if ((pipe (my_read) == -1) || (pipe (my_write) == -1))
    {
      g_message ("pipe() failed: Unable to start Plug-In \"%s\"\n(%s)",
                 g_path_get_basename (plug_in->args[0]),
                 plug_in->args[0]);
      return FALSE;
    }

#if defined(G_WITH_CYGWIN) || defined(__EMX__)
  /* Set to binary mode */
  setmode (my_read[0], _O_BINARY);
  setmode (my_write[0], _O_BINARY);
  setmode (my_read[1], _O_BINARY);
  setmode (my_write[1], _O_BINARY);
#endif

  plug_in->my_read   = g_io_channel_unix_new (my_read[0]);
  plug_in->my_write  = g_io_channel_unix_new (my_write[1]);
  plug_in->his_read  = g_io_channel_unix_new (my_write[0]);
  plug_in->his_write = g_io_channel_unix_new (my_read[1]);

  g_io_channel_set_encoding (plug_in->my_read, NULL, NULL);
  g_io_channel_set_encoding (plug_in->my_write, NULL, NULL);
  g_io_channel_set_encoding (plug_in->his_read, NULL, NULL);
  g_io_channel_set_encoding (plug_in->his_write, NULL, NULL);

  g_io_channel_set_buffered (plug_in->my_read, FALSE);
  g_io_channel_set_buffered (plug_in->my_write, FALSE);
  g_io_channel_set_buffered (plug_in->his_read, FALSE);
  g_io_channel_set_buffered (plug_in->his_write, FALSE);

  g_io_channel_set_close_on_unref (plug_in->my_read, TRUE);
  g_io_channel_set_close_on_unref (plug_in->my_write, TRUE);
  g_io_channel_set_close_on_unref (plug_in->his_read, TRUE);
  g_io_channel_set_close_on_unref (plug_in->his_write, TRUE);

  /* Remember the file descriptors for the pipes.
   */
  plug_in->args[2] =
    g_strdup_printf ("%d", g_io_channel_unix_get_fd (plug_in->his_read));
  plug_in->args[3] =
    g_strdup_printf ("%d", g_io_channel_unix_get_fd (plug_in->his_write));

  /* Set the rest of the command line arguments.
   * FIXME: this is ugly.  Pass in the mode as a separate argument?
   */
  if (plug_in->query)
    {
      plug_in->args[4] = g_strdup ("-query");
    }
  else if (plug_in->init)
    {
      plug_in->args[4] = g_strdup ("-init");
    }
  else  
    {
      plug_in->args[4] = g_strdup ("-run");
    }

  plug_in->args[5] = g_strdup_printf ("%d", plug_in->gimp->stack_trace_mode);

#ifdef __EMX__
  fcntl (my_read[0], F_SETFD, 1);
  fcntl (my_write[1], F_SETFD, 1);
#endif

  /* Fork another process. We'll remember the process id so that we
   * can later use it to kill the filter if necessary.
   */
  envp = gimp_environ_table_get_envp (plug_in->gimp->environ_table);
  if (! g_spawn_async (NULL, plug_in->args, envp,
                       G_SPAWN_LEAVE_DESCRIPTORS_OPEN |
                       G_SPAWN_DO_NOT_REAP_CHILD,
                       plug_in_prep_for_exec, plug_in,
                       &plug_in->pid,
                       &error))
    {
      g_message ("Unable to run Plug-In: \"%s\"\n(%s)\n%s",
                 g_path_get_basename (plug_in->args[0]),
                 plug_in->args[0],
                 error->message);
      g_error_free (error);
      return FALSE;
    }

  g_io_channel_unref (plug_in->his_read);
  plug_in->his_read = NULL;

  g_io_channel_unref (plug_in->his_write);
  plug_in->his_write = NULL;

  if (! plug_in->synchronous)
    {
      plug_in->input_id = g_io_add_watch (plug_in->my_read,
                                          G_IO_IN  | G_IO_PRI |
                                          G_IO_ERR | G_IO_HUP,
                                          plug_in_recv_message,
                                          plug_in);

      open_plug_ins = g_slist_prepend (open_plug_ins, plug_in);
    }

  plug_in->open = TRUE;
  return TRUE;
}

void
plug_in_close (PlugIn   *plug_in,
	       gboolean  kill_it)
{
  gint status;
#ifndef G_OS_WIN32
  struct timeval tv;
#endif

  g_return_if_fail (plug_in != NULL);
  g_return_if_fail (plug_in->open == TRUE);

  if (! plug_in->open)
    return;

  plug_in->open = FALSE;

  /*  Ask the filter to exit gracefully  */
  if (kill_it && plug_in->pid)
    {
      gp_quit_write (plug_in->my_write, plug_in);

      /*  give the plug-in some time (10 ms)  */
#ifndef G_OS_WIN32
      tv.tv_sec  = 0;
      tv.tv_usec = 100;	/* But this is 0.1 ms? */
      select (0, NULL, NULL, NULL, &tv);
#else
      Sleep (10);
#endif
    }

  /* If necessary, kill the filter. */
#ifndef G_OS_WIN32
  if (kill_it && plug_in->pid)
    status = kill (plug_in->pid, SIGKILL);

  /* Wait for the process to exit. This will happen
   *  immediately if it was just killed.
   */
  if (plug_in->pid)
    waitpid (plug_in->pid, &status, 0);
#else
  if (kill_it && plug_in->pid)
    {
      /* Trying to avoid TerminateProcess (does mostly work).
       * Otherwise some of our needed DLLs may get into an unstable state
       * (see Win32 API docs).
       */
      DWORD dwExitCode = STILL_ACTIVE;
      DWORD dwTries  = 10;
      while ((STILL_ACTIVE == dwExitCode)
	     && GetExitCodeProcess ((HANDLE) plug_in->pid, &dwExitCode)
	     && (dwTries > 0))
	{
	  Sleep(10);
	  dwTries--;
	}
      if (STILL_ACTIVE == dwExitCode)
	{
	  g_warning ("Terminating %s ...", plug_in->args[0]);
	  TerminateProcess ((HANDLE) plug_in->pid, 0);
	}
    }
#endif

  plug_in->pid = 0;

  /* Remove the input handler. */
  if (plug_in->input_id)
    {
      g_source_remove (plug_in->input_id);
      plug_in->input_id = 0;
    }

  /* Close the pipes. */
  if (plug_in->my_read != NULL)
    {
      g_io_channel_unref (plug_in->my_read);
      plug_in->my_read = NULL;
    }
  if (plug_in->my_write != NULL)
    {
      g_io_channel_unref (plug_in->my_write);
      plug_in->my_write = NULL;
    }
  if (plug_in->his_read != NULL)
    {
      g_io_channel_unref (plug_in->his_read);
      plug_in->his_read = NULL;
    }
  if (plug_in->his_write != NULL)
    {
      g_io_channel_unref (plug_in->his_write);
      plug_in->his_write = NULL;
    }

  wire_clear_error ();

  if (plug_in->progress)
    plug_in_progress_end (plug_in);

  if (plug_in->recurse)
    {
      while (plug_in->main_loops)
        {
          g_warning ("plug_in_close: quitting stale main loop\n");
          plug_in_main_loop_quit (plug_in);
        }

      plug_in->recurse = FALSE;
    }

  plug_in->synchronous = FALSE;

  /* Unregister any temporary procedures. */
  if (plug_in->temp_proc_defs)
    {
      GSList *list;

      for (list = plug_in->temp_proc_defs; list; list = g_slist_next (list))
        plug_ins_temp_proc_def_remove (plug_in->gimp,
                                       (PlugInProcDef *) list->data);

      g_slist_free (plug_in->temp_proc_defs);
      plug_in->temp_proc_defs = NULL;
    }

  /* Close any dialogs that this plugin might have opened */
  brush_select_dialogs_check ();
  gradient_select_dialogs_check ();
  palette_select_dialogs_check ();
  pattern_select_dialogs_check ();

  open_plug_ins = g_slist_remove (open_plug_ins, plug_in);
}

static gboolean
plug_in_recv_message (GIOChannel   *channel,
		      GIOCondition  cond,
		      gpointer	    data)
{
  PlugIn   *plug_in;
  gboolean  got_message = FALSE;

  plug_in = (PlugIn *) data;

  if (plug_in->my_read == NULL)
    return TRUE;

  if (cond & (G_IO_IN | G_IO_PRI))
    {
      WireMessage msg;

      memset (&msg, 0, sizeof (WireMessage));

      if (! wire_read_msg (plug_in->my_read, &msg, plug_in))
	{
	  plug_in_close (plug_in, TRUE);
	}
      else
	{
	  plug_in_handle_message (plug_in, &msg);
	  wire_destroy (&msg);
	  got_message = TRUE;
	}
    }

  if (cond & (G_IO_ERR | G_IO_HUP))
    {
      if (plug_in->open)
	{
	  plug_in_close (plug_in, TRUE);
	}
    }

  if (! got_message)
    g_message (_("Plug-In crashed: \"%s\"\n(%s)\n\n"
		 "The dying Plug-In may have messed up GIMP's internal state.\n"
		 "You may want to save your images and restart GIMP\n"
		 "to be on the safe side."),
	       g_path_get_basename (plug_in->args[0]),
	       plug_in->args[0]);

  if (! plug_in->open)
    plug_in_unref (plug_in);

  return TRUE;
}

static gboolean
plug_in_write (GIOChannel *channel,
	       guint8      *buf,
	       gulong       count,
               gpointer     user_data)
{
  PlugIn *plug_in;
  gulong  bytes;

  plug_in = (PlugIn *) user_data;

  while (count > 0)
    {
      if ((plug_in->write_buffer_index + count) >= WRITE_BUFFER_SIZE)
	{
	  bytes = WRITE_BUFFER_SIZE - plug_in->write_buffer_index;
	  memcpy (&plug_in->write_buffer[plug_in->write_buffer_index],
                  buf, bytes);
	  plug_in->write_buffer_index += bytes;
	  if (! wire_flush (channel, plug_in))
	    return FALSE;
	}
      else
	{
	  bytes = count;
	  memcpy (&plug_in->write_buffer[plug_in->write_buffer_index],
                  buf, bytes);
	  plug_in->write_buffer_index += bytes;
	}

      buf += bytes;
      count -= bytes;
    }

  return TRUE;
}

static gboolean
plug_in_flush (GIOChannel *channel,
               gpointer    user_data)
{
  PlugIn *plug_in;

  plug_in = (PlugIn *) user_data;

  if (plug_in->write_buffer_index > 0)
    {
      GIOStatus  status;
      GError    *error = NULL;
      gint       count;
      gsize      bytes;

      count = 0;
      while (count != plug_in->write_buffer_index)
        {
	  do
	    {
	      bytes = 0;
	      status = g_io_channel_write_chars (channel,
						 &plug_in->write_buffer[count],
						 (plug_in->write_buffer_index - count),
						 &bytes,
						 &error);
	    }
	  while (status == G_IO_STATUS_AGAIN);

	  if (status != G_IO_STATUS_NORMAL)
	    {
	      if (error)
		{
		  g_warning ("%s: plug_in_flush(): error: %s",
			     g_get_prgname (), error->message);
		  g_error_free (error);
		}
	      else
		{
		  g_warning ("%s: plug_in_flush(): error",
			     g_get_prgname ());
		}

	      return FALSE;
	    }

          count += bytes;
        }

      plug_in->write_buffer_index = 0;
    }

  return TRUE;
}

void
plug_in_push (PlugIn *plug_in)
{
  g_return_if_fail (plug_in != NULL);

  current_plug_in = plug_in;

  plug_in_stack = g_slist_prepend (plug_in_stack, current_plug_in);
}

void
plug_in_pop (void)
{
  GSList *tmp;

  if (current_plug_in)
    {
      tmp = plug_in_stack;
      plug_in_stack = plug_in_stack->next;
      tmp->next = NULL;
      g_slist_free (tmp);
    }

  if (plug_in_stack)
    {
      current_plug_in = plug_in_stack->data;
    }
  else
    {
      current_plug_in = NULL;
    }
}

void
plug_in_main_loop (PlugIn *plug_in)
{
  GMainLoop *main_loop;

  g_return_if_fail (plug_in != NULL);

  main_loop = g_main_loop_new (NULL, FALSE);

  plug_in->main_loops = g_list_prepend (plug_in->main_loops, main_loop);

  gimp_threads_leave (plug_in->gimp);
  g_main_loop_run (main_loop);
  gimp_threads_enter (plug_in->gimp);

  g_main_loop_unref (main_loop);
}

void
plug_in_main_loop_quit (PlugIn *plug_in)
{
  g_return_if_fail (plug_in != NULL);

  if (! plug_in->main_loops)
    {
      g_warning ("plug_in_main_loop_quit: called without a main loop running");
      return;
    }

  g_main_loop_quit ((GMainLoop *) plug_in->main_loops->data);

  plug_in->main_loops = g_list_remove (plug_in->main_loops,
                                       plug_in->main_loops->data);
}