Rename GtkGS to PSDocument

2005-01-01  Marco Pesenti Gritti  <marco@gnome.org>

        * ps/Makefile.am:
        * ps/gstypes.h:
        * ps/gtkgs.c:
        * ps/gtkgs.h:
        * ps/ps-document.c: (catchPipe), (ps_document_init),
        (ps_document_class_init), (ps_document_cleanup),
        (ps_document_finalize), (send_ps), (ps_document_get_orientation),
        (set_up_page), (close_pipe), (is_interpreter_ready),
        (interpreter_failed), (output), (input), (start_interpreter),
        (stop_interpreter), (file_length), (file_readable),
        (check_filecompressed), (check_pdf), (compute_xdpi),
        (compute_ydpi), (compute_size), (ps_document_enable_interpreter),
        (ps_document_get_type), (ps_document_emit_error_msg),
        (document_load), (ps_document_next_page),
        (ps_document_get_current_page), (ps_document_get_page_count),
        (ps_document_goto_page), (ps_document_set_page_size),
        (ps_document_zoom_to_fit), (ps_document_set_zoom),
        (ps_document_load), (ps_document_get_n_pages),
        (ps_document_set_page), (ps_document_get_page),
        (ps_document_widget_event), (ps_document_set_target),
        (ps_document_set_scale), (ps_document_set_page_offset),
        (ps_document_get_page_size), (ps_document_render),
        (ps_document_document_iface_init):
        * ps/ps-document.h:
        * ps/ps.c:
        * shell/ev-window.c: (ev_window_open):

        Rename GtkGS to PSDocument

1 files changed, 1777 insertions, 0 deletions

diff --git a/ps/ps-document.c b/ps/ps-document.c
new file mode 100644
index 0000000..7619f03
--- /dev/null
+++ b/ps/ps-document.c
@@ -0,0 +1,1777 @@
+/* Ghostscript widget for GTK/GNOME
+ * 
+ * Copyright (C) 1998 - 2005 the Free Software Foundation
+ * 
+ * Authors: Jonathan Blandford, Jaka Mocnik
+ * 
+ * Based on code by: Federico Mena (Quartic), Szekeres Istvan (Pista)
+ *
+ * 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., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+ 
+/*
+Ghostview interface to ghostscript
+
+When the GHOSTVIEW environment variable is set, ghostscript draws on
+an existing drawable rather than creating its own window.  Ghostscript
+can be directed to draw on either a window or a pixmap.
+
+Drawing on a Window
+
+The GHOSTVIEW environment variable contains the window id of the target
+window.  The window id is an integer.  Ghostscript will use the attributes
+of the window to obtain the width, height, colormap, screen, and visual of
+the window. The remainder of the information is gotten from the GHOSTVIEW
+property on that window.
+
+
+Drawing on a Pixmap
+
+The GHOSTVIEW environment variable contains a window id and a pixmap id.
+They are integers separated by white space.  Ghostscript will use the
+attributes of the window to obtain the colormap, screen, and visual to use.
+The width and height will be obtained from the pixmap. The remainder of the
+information, is gotten from the GHOSTVIEW property on the window.  In this
+case, the property is deleted when read.
+
+The GHOSTVIEW environment variable
+
+parameters:	window-id [pixmap-id]
+
+scanf format:	"%d %d"
+
+explanation of parameters:
+
+	window-id: tells ghostscript where to
+		    - read the GHOSTVIEW property
+		    - send events
+		    If pixmap-id is not present,
+		    ghostscript will draw on this window.
+
+	pixmap-id: If present, tells ghostscript that a pixmap will be used
+		    as the final destination for drawing.  The window will
+		    not be touched for drawing purposes.
+
+The GHOSTVIEW property
+
+type:	STRING
+
+parameters:
+
+    bpixmap orient llx lly urx ury xdpi ydpi [left bottom top right]
+
+scanf format: "%d %d %d %d %d %d %f %f %d %d %d %d"
+
+explanation of parameters:
+
+	bpixmap: pixmap id of the backing pixmap for the window.  If no
+		pixmap is to be used, this parameter should be zero.  This
+		parameter must be zero when drawing on a pixmap.
+
+	orient:	orientation of the page.  The number represents clockwise
+		rotation of the paper in degrees.  Permitted values are
+		0, 90, 180, 270.
+
+	llx, lly, urx, ury: Bounding box of the drawable.  The bounding box
+		is specified in PostScript points in default user coordinates.
+
+	xdpi, ydpi: Resolution of window.  (This can be derived from the
+		other parameters, but not without roundoff error.  These
+		values are included to avoid this error.)
+
+	left, bottom, top, right: (optional)
+		Margins around the window.  The margins extend the imageable
+		area beyond the boundaries of the window.  This is primarily
+		used for popup zoom windows.  I have encountered several
+		instances of PostScript programs that position themselves
+		with respect to the imageable area.  The margins are specified
+		in PostScript points.  If omitted, the margins are assumed to
+		be 0.
+
+Events from ghostscript
+
+If the final destination is a pixmap, the client will get a property notify
+event when ghostscript reads the GHOSTVIEW property causing it to be deleted.
+
+Ghostscript sends events to the window where it read the GHOSTVIEW property.
+These events are of type ClientMessage.  The message_type is set to
+either PAGE or DONE.  The first long data value gives the window to be used
+to send replies to ghostscript.  The second long data value gives the primary
+drawable.  If rendering to a pixmap, it is the primary drawable.  If rendering
+to a window, the backing pixmap is the primary drawable.  If no backing pixmap
+is employed, then the window is the primary drawable.  This field is necessary
+to distinguish multiple ghostscripts rendering to separate pixmaps where the
+GHOSTVIEW property was placed on the same window.
+
+The PAGE message indicates that a "page" has completed.  Ghostscript will
+wait until it receives a ClientMessage whose message_type is NEXT before
+continuing.
+
+The DONE message indicates that ghostscript has finished processing.
+
+*/
+
+#include "config.h"
+#include <string.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <gtk/gtk.h>
+#include <gtk/gtkobject.h>
+#include <gdk/gdkprivate.h>
+#include <gdk/gdkx.h>
+#include <gdk/gdk.h>
+#include <glib/gi18n.h>
+#ifdef  HAVE_XINERAMA
+#   include <gdk/gdkx.h>
+#   include <X11/extensions/Xinerama.h>
+#endif /* HAVE_XINERAMA */
+#include <X11/Intrinsic.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <stdio.h>
+#include <math.h>
+
+#include "ev-document.h"
+#include "ps-document.h"
+#include "ps.h"
+#include "gsdefaults.h"
+
+#ifdef HAVE_LOCALE_H
+#   include <locale.h>
+#endif
+
+/* if POSIX O_NONBLOCK is not available, use O_NDELAY */
+#if !defined(O_NONBLOCK) && defined(O_NDELAY)
+#   define O_NONBLOCK O_NDELAY
+#endif
+
+#define PS_DOCUMENT_WATCH_INTERVAL 1000
+#define PS_DOCUMENT_WATCH_TIMEOUT  2
+
+#define MAX_BUFSIZE 1024
+
+#define PS_DOCUMENT_IS_COMPRESSED(gs)       (PS_DOCUMENT(gs)->gs_filename_unc != NULL)
+#define PS_DOCUMENT_GET_PS_FILE(gs)         (PS_DOCUMENT_IS_COMPRESSED(gs) ? \
+                                        PS_DOCUMENT(gs)->gs_filename_unc : \
+                                        PS_DOCUMENT(gs)->gs_filename)
+
+enum { INTERPRETER_MESSAGE, INTERPRETER_ERROR, LAST_SIGNAL };
+
+/* structure to describe section of file to send to ghostscript */
+struct record_list {
+  FILE *fp;
+  long begin;
+  guint len;
+  gboolean seek_needed;
+  gboolean close;
+  struct record_list *next;
+};
+
+static gboolean broken_pipe = FALSE;
+
+static void
+catchPipe(int i)
+{
+  broken_pipe = True;
+}
+
+/* Forward declarations */
+static void ps_document_init(PSDocument * gs);
+static void ps_document_class_init(PSDocumentClass * klass);
+static void ps_document_emit_error_msg(PSDocument * gs, const gchar * msg);
+static void ps_document_finalize(GObject * object);
+static void send_ps(PSDocument * gs, long begin, unsigned int len, gboolean close);
+static void set_up_page(PSDocument * gs);
+static void close_pipe(int p[2]);
+static void interpreter_failed(PSDocument * gs);
+static float compute_xdpi(void);
+static float compute_ydpi(void);
+static gboolean compute_size(PSDocument * gs);
+static void output(gpointer data, gint source, GdkInputCondition condition);
+static void input(gpointer data, gint source, GdkInputCondition condition);
+static void stop_interpreter(PSDocument * gs);
+static gint start_interpreter(PSDocument * gs);
+gboolean computeSize(void);
+static gboolean ps_document_set_page_size(PSDocument * gs, gint new_pagesize, gint pageid);
+static void ps_document_document_iface_init (EvDocumentIface *iface);
+
+static GObjectClass *parent_class = NULL;
+
+static PSDocumentClass *gs_class = NULL;
+
+static void
+ps_document_init(PSDocument * gs)
+{
+  gs->bpixmap = NULL;
+
+  gs->current_page = -2;
+  gs->disable_start = FALSE;
+  gs->interpreter_pid = -1;
+
+  gs->width = -1;
+  gs->height = -1;
+  gs->busy = FALSE;
+  gs->changed = FALSE;
+  gs->gs_scanstyle = 0;
+  gs->gs_filename = 0;
+  gs->gs_filename_dsc = 0;
+  gs->gs_filename_unc = 0;
+
+  broken_pipe = FALSE;
+
+  gs->structured_doc = FALSE;
+  gs->reading_from_pipe = FALSE;
+  gs->send_filename_to_gs = FALSE;
+
+  gs->doc = NULL;
+  gs->loaded = FALSE;
+
+  gs->interpreter_input = -1;
+  gs->interpreter_output = -1;
+  gs->interpreter_err = -1;
+  gs->interpreter_input_id = 0;
+  gs->interpreter_output_id = 0;
+  gs->interpreter_error_id = 0;
+
+  gs->ps_input = NULL;
+  gs->input_buffer = NULL;
+  gs->input_buffer_ptr = NULL;
+  gs->bytes_left = 0;
+  gs->buffer_bytes_left = 0;
+
+  gs->llx = 0;
+  gs->lly = 0;
+  gs->urx = 0;
+  gs->ury = 0;
+  gs->xdpi = compute_xdpi();
+  gs->ydpi = compute_ydpi();
+
+  gs->left_margin = 0;
+  gs->top_margin = 0;
+  gs->right_margin = 0;
+  gs->bottom_margin = 0;
+
+  /* Set user defined defaults */
+  gs->override_orientation = gtk_gs_defaults_get_override_orientation();
+  gs->fallback_orientation = gtk_gs_defaults_get_orientation();
+  gs->zoom_factor = gtk_gs_defaults_get_zoom_factor();
+  gs->default_size = gtk_gs_defaults_get_size();
+  gs->antialiased = gtk_gs_defaults_get_antialiased();
+  gs->override_size = gtk_gs_defaults_get_override_size();
+  gs->respect_eof = gtk_gs_defaults_get_respect_eof();
+  gs->zoom_mode = gtk_gs_defaults_get_zoom_mode();
+
+  gs->gs_status = _("No document loaded.");
+}
+
+static void
+ps_document_class_init(PSDocumentClass * klass)
+{
+  GObjectClass *object_class;
+
+  object_class = (GObjectClass *) klass;
+  parent_class = gtk_type_class(gtk_widget_get_type());
+  gs_class = klass;
+
+  object_class->finalize = ps_document_finalize;
+
+  /* Create atoms */
+  klass->gs_atom = gdk_atom_intern("GHOSTVIEW", FALSE);
+  klass->next_atom = gdk_atom_intern("NEXT", FALSE);
+  klass->page_atom = gdk_atom_intern("PAGE", FALSE);
+  klass->string_atom = gdk_atom_intern("STRING", FALSE);
+
+  gtk_gs_defaults_load();
+}
+
+/* Clean all memory and temporal files */
+static void
+ps_document_cleanup(PSDocument * gs)
+{
+  g_return_if_fail(gs != NULL);
+  g_return_if_fail(GTK_IS_GS(gs));
+
+  stop_interpreter(gs);
+
+  if(gs->gs_psfile) {
+    fclose(gs->gs_psfile);
+    gs->gs_psfile = NULL;
+  }
+  if(gs->gs_filename) {
+    g_free(gs->gs_filename);
+    gs->gs_filename = NULL;
+  }
+  if(gs->doc) {
+    psfree(gs->doc);
+    gs->doc = NULL;
+  }
+  if(gs->gs_filename_dsc) {
+    unlink(gs->gs_filename_dsc);
+    g_free(gs->gs_filename_dsc);
+    gs->gs_filename_dsc = NULL;
+  }
+  if(gs->gs_filename_unc) {
+    unlink(gs->gs_filename_unc);
+    g_free(gs->gs_filename_unc);
+    gs->gs_filename_unc = NULL;
+  }
+  gs->current_page = -1;
+  gs->loaded = FALSE;
+  gs->llx = 0;
+  gs->lly = 0;
+  gs->urx = 0;
+  gs->ury = 0;
+  set_up_page(gs);
+}
+
+static void
+ps_document_finalize(GObject * object)
+{
+  PSDocument *gs;
+
+  g_return_if_fail(object != NULL);
+  g_return_if_fail(GTK_IS_GS(object));
+
+  gs = PS_DOCUMENT(object);
+
+  ps_document_cleanup(gs);
+
+  if(gs->input_buffer) {
+    g_free(gs->input_buffer);
+    gs->input_buffer = NULL;
+  }
+
+  (*G_OBJECT_CLASS(parent_class)->finalize) (object);
+}
+
+static void
+send_ps(PSDocument * gs, long begin, unsigned int len, gboolean close)
+{
+  struct record_list *ps_new;
+
+  if(gs->interpreter_input < 0) {
+    g_critical("No pipe to gs: error in send_ps().");
+    return;
+  }
+
+  ps_new = (struct record_list *) g_malloc(sizeof(struct record_list));
+  ps_new->fp = gs->gs_psfile;
+  ps_new->begin = begin;
+  ps_new->len = len;
+  ps_new->seek_needed = TRUE;
+  ps_new->close = close;
+  ps_new->next = NULL;
+
+  if(gs->input_buffer == NULL) {
+    gs->input_buffer = g_malloc(MAX_BUFSIZE);
+  }
+
+  if(gs->ps_input == NULL) {
+    gs->input_buffer_ptr = gs->input_buffer;
+    gs->bytes_left = len;
+    gs->buffer_bytes_left = 0;
+    gs->ps_input = ps_new;
+    gs->interpreter_input_id =
+      gdk_input_add(gs->interpreter_input, GDK_INPUT_WRITE, input, gs);
+  }
+  else {
+    struct record_list *p = gs->ps_input;
+    while(p->next != NULL) {
+      p = p->next;
+    }
+    p->next = ps_new;
+  }
+}
+
+static gint
+ps_document_get_orientation(PSDocument * gs)
+{
+  g_return_val_if_fail(gs != NULL, -1);
+  g_return_val_if_fail(GTK_IS_GS(gs), -1);
+
+  if(gs->doc) {
+    if(gs->structured_doc) {
+      if(gs->doc->pages[MAX(gs->current_page, 0)].orientation !=
+         GTK_GS_ORIENTATION_NONE)
+        gs->real_orientation =
+          gs->doc->pages[MAX(gs->current_page, 0)].orientation;
+      else
+        gs->real_orientation = gs->doc->default_page_orientation;
+    }
+
+    if(gs->real_orientation == GTK_GS_ORIENTATION_NONE)
+      gs->real_orientation = gs->doc->orientation;
+  }
+
+  if(gs->override_orientation ||
+     gs->real_orientation == GTK_GS_ORIENTATION_NONE)
+    return gs->fallback_orientation;
+  else
+    return gs->real_orientation;
+}
+
+static void
+set_up_page(PSDocument * gs)
+{
+  guint orientation;
+  char buf[1024];
+  //GdkColormap *colormap;
+  GdkGC *fill;
+  GdkColor white = { 0, 0xFFFF, 0xFFFF, 0xFFFF };   /* pixel, r, g, b */
+  GdkColormap *colormap;
+
+#ifdef HAVE_LOCALE_H
+  char *savelocale;
+#endif
+
+  if (gs->pstarget == NULL)
+    return;
+
+  /* Do we have to check if the actual geometry changed? */
+
+  stop_interpreter(gs);
+
+  orientation = ps_document_get_orientation(gs);
+
+  if(compute_size(gs)) {
+    gdk_flush();
+
+    /* clear new pixmap (set to white) */
+    fill = gdk_gc_new(gs->pstarget);
+    if(fill) {
+      colormap = gdk_drawable_get_colormap(gs->pstarget);
+      gdk_color_alloc (colormap, &white);
+      gdk_gc_set_foreground(fill, &white);
+
+      if(gs->width > 0 && gs->height > 0) {
+        if(gs->bpixmap) {
+          gdk_drawable_unref(gs->bpixmap);
+          gs->bpixmap = NULL;
+        }
+
+        gs->bpixmap = gdk_pixmap_new(gs->pstarget, gs->width, gs->height, -1);
+
+        gdk_draw_rectangle(gs->bpixmap, fill, TRUE,
+                           0, 0, gs->width, gs->height);
+      }
+      else {
+        gdk_draw_rectangle(gs->pstarget, fill, TRUE,
+                           0, 0, gs->width, gs->height);
+      }
+      gdk_gc_unref(fill);
+
+      gdk_flush();
+    }
+  }
+
+#ifdef HAVE_LOCALE_H
+  /* gs needs floating point parameters with '.' as decimal point
+   * while some (european) locales use ',' instead, so we set the 
+   * locale for this snprintf to "C".
+   */
+  savelocale = setlocale(LC_NUMERIC, "C");
+#endif
+
+  g_snprintf(buf, 1024, "%ld %d %d %d %d %d %f %f %d %d %d %d",
+             0L,
+             orientation * 90,
+             gs->llx,
+             gs->lly,
+             gs->urx,
+             gs->ury,
+             gs->xdpi * gs->zoom_factor,
+             gs->ydpi * gs->zoom_factor,
+             gs->left_margin,
+             gs->bottom_margin, gs->right_margin, gs->top_margin);
+
+#ifdef HAVE_LOCALE_H
+  setlocale(LC_NUMERIC, savelocale);
+#endif
+  gdk_property_change(gs->pstarget,
+                      gs_class->gs_atom,
+                      gs_class->string_atom,
+                      8, GDK_PROP_MODE_REPLACE, buf, strlen(buf));
+  gdk_flush();
+}
+
+static void
+close_pipe(int p[2])
+{
+  if(p[0] != -1)
+    close(p[0]);
+  if(p[1] != -1)
+    close(p[1]);
+}
+
+static gboolean
+is_interpreter_ready(PSDocument * gs)
+{
+  return (gs->interpreter_pid != -1 && !gs->busy && gs->ps_input == NULL);
+}
+
+static void
+interpreter_failed(PSDocument * gs)
+{
+  stop_interpreter(gs);
+}
+
+static void
+output(gpointer data, gint source, GdkInputCondition condition)
+{
+  char buf[MAX_BUFSIZE + 1], *msg;
+  guint bytes = 0;
+  PSDocument *gs = PS_DOCUMENT(data);
+
+  if(source == gs->interpreter_output) {
+    bytes = read(gs->interpreter_output, buf, MAX_BUFSIZE);
+    if(bytes == 0) {            /* EOF occurred */
+      close(gs->interpreter_output);
+      gs->interpreter_output = -1;
+      gdk_input_remove(gs->interpreter_output_id);
+      return;
+    }
+    else if(bytes == -1) {
+      /* trouble... */
+      interpreter_failed(gs);
+      return;
+    }
+    if(gs->interpreter_err == -1) {
+      stop_interpreter(gs);
+    }
+  }
+  else if(source == gs->interpreter_err) {
+    bytes = read(gs->interpreter_err, buf, MAX_BUFSIZE);
+    if(bytes == 0) {            /* EOF occurred */
+      close(gs->interpreter_err);
+      gs->interpreter_err = -1;
+      gdk_input_remove(gs->interpreter_error_id);
+      return;
+    }
+    else if(bytes == -1) {
+      /* trouble... */
+      interpreter_failed(gs);
+      return;
+    }
+    if(gs->interpreter_output == -1) {
+      stop_interpreter(gs);
+    }
+  }
+  if(bytes > 0) {
+    buf[bytes] = '\0';
+    msg = g_strdup(buf);
+    ps_document_emit_error_msg (gs, msg);   
+  }
+}
+
+static void
+input(gpointer data, gint source, GdkInputCondition condition)
+{
+  PSDocument *gs = PS_DOCUMENT(data);
+  int bytes_written;
+  void (*oldsig) (int);
+  oldsig = signal(SIGPIPE, catchPipe);
+
+  do {
+    if(gs->buffer_bytes_left == 0) {
+      /* Get a new section if required */
+      if(gs->ps_input && gs->bytes_left == 0) {
+        struct record_list *ps_old = gs->ps_input;
+        gs->ps_input = ps_old->next;
+        if(ps_old->close && NULL != ps_old->fp)
+          fclose(ps_old->fp);
+        g_free((char *) ps_old);
+      }
+      /* Have to seek at the beginning of each section */
+      if(gs->ps_input && gs->ps_input->seek_needed) {
+        fseek(gs->ps_input->fp, gs->ps_input->begin, SEEK_SET);
+        gs->ps_input->seek_needed = FALSE;
+        gs->bytes_left = gs->ps_input->len;
+      }
+
+      if(gs->bytes_left > MAX_BUFSIZE) {
+        gs->buffer_bytes_left =
+          fread(gs->input_buffer, sizeof(char), MAX_BUFSIZE, gs->ps_input->fp);
+      }
+      else if(gs->bytes_left > 0) {
+        gs->buffer_bytes_left =
+          fread(gs->input_buffer,
+                sizeof(char), gs->bytes_left, gs->ps_input->fp);
+      }
+      else {
+        gs->buffer_bytes_left = 0;
+      }
+      if(gs->bytes_left > 0 && gs->buffer_bytes_left == 0) {
+        interpreter_failed(gs); /* Error occurred */
+      }
+      gs->input_buffer_ptr = gs->input_buffer;
+      gs->bytes_left -= gs->buffer_bytes_left;
+    }
+
+    if(gs->buffer_bytes_left > 0) {
+      /* g_print (" writing: %s\n",gs->input_buffer_ptr); */
+
+      bytes_written = write(gs->interpreter_input,
+                            gs->input_buffer_ptr, gs->buffer_bytes_left);
+
+      if(broken_pipe) {
+        ps_document_emit_error_msg(gs, g_strdup(_("Broken pipe.")));
+        broken_pipe = FALSE;
+        interpreter_failed(gs);
+      }
+      else if(bytes_written == -1) {
+        if((errno != EWOULDBLOCK) && (errno != EAGAIN)) {
+          interpreter_failed(gs);   /* Something bad happened */
+        }
+      }
+      else {
+        gs->buffer_bytes_left -= bytes_written;
+        gs->input_buffer_ptr += bytes_written;
+      }
+    }
+  }
+  while(gs->ps_input && gs->buffer_bytes_left == 0);
+
+  signal(SIGPIPE, oldsig);
+
+  if(gs->ps_input == NULL && gs->buffer_bytes_left == 0) {
+    if(gs->interpreter_input_id != 0) {
+      gdk_input_remove(gs->interpreter_input_id);
+      gs->interpreter_input_id = 0;
+    }
+  }
+}
+
+static int
+start_interpreter(PSDocument * gs)
+{
+  int std_in[2] = { -1, -1 };   /* pipe to interp stdin */
+  int std_out[2];               /* pipe from interp stdout */
+  int std_err[2];               /* pipe from interp stderr */
+
+#define NUM_ARGS    100
+#define NUM_GS_ARGS (NUM_ARGS - 20)
+#define NUM_ALPHA_ARGS 10
+
+  char *argv[NUM_ARGS], *dir, *gv_env;
+  char **gs_args, **alpha_args = NULL;
+  int argc = 0, i;
+
+  if(!gs->gs_filename)
+    return 0;
+
+  stop_interpreter(gs);
+
+  if(gs->disable_start == TRUE)
+    return 0;
+
+  /* set up the args... */
+  gs_args = g_strsplit(gtk_gs_defaults_get_interpreter_cmd(), " ", NUM_GS_ARGS);
+  for(i = 0; i < NUM_GS_ARGS && gs_args[i]; i++, argc++)
+    argv[argc] = gs_args[i];
+
+  if(gs->antialiased) {
+    if(strlen(gtk_gs_defaults_get_alpha_parameters()) == 0)
+      alpha_args = g_strsplit(ALPHA_PARAMS, " ", NUM_ALPHA_ARGS);
+    else
+      alpha_args = g_strsplit(gtk_gs_defaults_get_alpha_parameters(),
+                              " ", NUM_ALPHA_ARGS);
+    for(i = 0; i < NUM_ALPHA_ARGS && alpha_args[i]; i++, argc++)
+      argv[argc] = alpha_args[i];
+  }
+  else
+    argv[argc++] = "-sDEVICE=x11";
+  argv[argc++] = "-dNOPAUSE";
+  argv[argc++] = "-dQUIET";
+  /* I assume we do _not_ want to change this... (: */
+  argv[argc++] = "-dSAFER";
+
+  /* set up the pipes */
+  if(gs->send_filename_to_gs) {
+    argv[argc++] = PS_DOCUMENT_GET_PS_FILE(gs);
+    argv[argc++] = "-c";
+    argv[argc++] = "quit";
+  }
+  else
+    argv[argc++] = "-";
+
+  argv[argc++] = NULL;
+
+  if(!gs->reading_from_pipe && !gs->send_filename_to_gs) {
+    if(pipe(std_in) == -1) {
+      g_critical("Unable to open pipe to Ghostscript.");
+      return -1;
+    }
+  }
+  if(pipe(std_out) == -1) {
+    close_pipe(std_in);
+    return -1;
+  }
+  if(pipe(std_err) == -1) {
+    close_pipe(std_in);
+    close_pipe(std_out);
+    return -1;
+  }
+
+  gs->busy = TRUE;
+  gs->interpreter_pid = fork();
+  switch (gs->interpreter_pid) {
+  case -1:                     /* error */
+    close_pipe(std_in);
+    close_pipe(std_out);
+    close_pipe(std_err);
+    return -2;
+    break;
+  case 0:                      /* child */
+    close(std_out[0]);
+    dup2(std_out[1], 1);
+    close(std_out[1]);
+
+    close(std_err[0]);
+    dup2(std_err[1], 2);
+    close(std_err[1]);
+
+    if(!gs->reading_from_pipe) {
+      if(gs->send_filename_to_gs) {
+        int stdinfd;
+        /* just in case gs tries to read from stdin */
+        stdinfd = open("/dev/null", O_RDONLY);
+        if(stdinfd != 0) {
+          dup2(stdinfd, 0);
+          close(stdinfd);
+        }
+      }
+      else {
+        close(std_in[1]);
+        dup2(std_in[0], 0);
+        close(std_in[0]);
+      }
+    }
+
+    gv_env = g_strdup_printf("GHOSTVIEW=%ld %ld",
+                             gdk_x11_drawable_get_xid(gs->pstarget),
+			     gdk_x11_drawable_get_xid(gs->bpixmap));
+    putenv(gv_env);
+
+    /* change to directory where the input file is. This helps
+     * with postscript-files which include other files using
+     * a relative path */
+    dir = g_path_get_dirname(gs->gs_filename);
+    chdir(dir);
+    g_free(dir);
+
+    execvp(argv[0], argv);
+
+    /* Notify error */
+    g_print("Unable to execute [%s]\n", argv[0]);
+    g_strfreev(gs_args);
+    g_free(gv_env);
+    if(alpha_args)
+      g_strfreev(alpha_args);
+    _exit(1);
+    break;
+  default:                     /* parent */
+    if(!gs->send_filename_to_gs && !gs->reading_from_pipe) {
+      int result;
+      close(std_in[0]);
+      /* use non-blocking IO for pipe to ghostscript */
+      result = fcntl(std_in[1], F_GETFL, 0);
+      fcntl(std_in[1], F_SETFL, result | O_NONBLOCK);
+      gs->interpreter_input = std_in[1];
+    }
+    else {
+      gs->interpreter_input = -1;
+    }
+    close(std_out[1]);
+    gs->interpreter_output = std_out[0];
+    close(std_err[1]);
+    gs->interpreter_err = std_err[0];
+    gs->interpreter_output_id =
+      gdk_input_add(std_out[0], GDK_INPUT_READ, output, gs);
+    gs->interpreter_error_id =
+      gdk_input_add(std_err[0], GDK_INPUT_READ, output, gs);
+    break;
+  }
+  return TRUE;
+}
+
+static void
+stop_interpreter(PSDocument * gs)
+{
+  if(gs->interpreter_pid > 0) {
+    int status = 0;
+    kill(gs->interpreter_pid, SIGTERM);
+    while((wait(&status) == -1) && (errno == EINTR)) ;
+    gs->interpreter_pid = -1;
+    if(status == 1) {
+      ps_document_cleanup(gs);
+      gs->gs_status = _("Interpreter failed.");
+    }
+  }
+
+  if(gs->interpreter_input >= 0) {
+    close(gs->interpreter_input);
+    gs->interpreter_input = -1;
+    if(gs->interpreter_input_id != 0) {
+      gdk_input_remove(gs->interpreter_input_id);
+      gs->interpreter_input_id = 0;
+    }
+    while(gs->ps_input) {
+      struct record_list *ps_old = gs->ps_input;
+      gs->ps_input = gs->ps_input->next;
+      if(ps_old->close && NULL != ps_old->fp)
+        fclose(ps_old->fp);
+      g_free((char *) ps_old);
+    }
+  }
+
+  if(gs->interpreter_output >= 0) {
+    close(gs->interpreter_output);
+    gs->interpreter_output = -1;
+    if(gs->interpreter_output_id) {
+      gdk_input_remove(gs->interpreter_output_id);
+      gs->interpreter_output_id = 0;
+    }
+  }
+
+  if(gs->interpreter_err >= 0) {
+    close(gs->interpreter_err);
+    gs->interpreter_err = -1;
+    if(gs->interpreter_error_id) {
+      gdk_input_remove(gs->interpreter_error_id);
+      gs->interpreter_error_id = 0;
+    }
+  }
+
+  gs->busy = FALSE;
+}
+
+/* If file exists and is a regular file then return its length, else -1 */
+static gint
+file_length(const gchar * filename)
+{
+  struct stat stat_rec;
+
+  if(filename && (stat(filename, &stat_rec) == 0)
+     && S_ISREG(stat_rec.st_mode))
+    return stat_rec.st_size;
+  else
+    return -1;
+}
+
+/* Test if file exists, is a regular file and its length is > 0 */
+static gboolean
+file_readable(const char *filename)
+{
+  return (file_length(filename) > 0);
+}
+
+/*
+ * Decompress gs->gs_filename if necessary
+ * Set gs->filename_unc to the name of the uncompressed file or NULL.
+ * Error reporting via signal 'interpreter_message'
+ * Return name of input file to use or NULL on error..
+ */
+static gchar *
+check_filecompressed(PSDocument * gs)
+{
+  FILE *file;
+  gchar buf[1024];
+  gchar *filename, *filename_unc, *filename_err, *cmdline;
+  const gchar *cmd;
+  int fd;
+
+  cmd = NULL;
+
+  if((file = fopen(gs->gs_filename, "r"))
+     && (fread(buf, sizeof(gchar), 3, file) == 3)) {
+    if((buf[0] == '\037') && ((buf[1] == '\235') || (buf[1] == '\213'))) {
+      /* file is gzipped or compressed */
+      cmd = gtk_gs_defaults_get_ungzip_cmd();
+    }
+    else if(strncmp(buf, "BZh", 3) == 0) {
+      /* file is compressed with bzip2 */
+      cmd = gtk_gs_defaults_get_unbzip2_cmd();
+    }
+  }
+  if(NULL != file)
+    fclose(file);
+
+  if(!cmd)
+    return gs->gs_filename;
+
+  /* do the decompression */
+  filename = g_shell_quote(gs->gs_filename);
+  filename_unc = g_strconcat(g_get_tmp_dir(), "/ggvXXXXXX", NULL);
+  if((fd = mkstemp(filename_unc)) < 0) {
+    g_free(filename_unc);
+    g_free(filename);
+    return NULL;
+  }
+  close(fd);
+  filename_err = g_strconcat(g_get_tmp_dir(), "/ggvXXXXXX", NULL);
+  if((fd = mkstemp(filename_err)) < 0) {
+    g_free(filename_err);
+    g_free(filename_unc);
+    g_free(filename);
+    return NULL;
+  }
+  close(fd);
+  cmdline = g_strdup_printf("%s %s >%s 2>%s", cmd,
+                            filename, filename_unc, filename_err);
+  if((system(cmdline) == 0)
+     && file_readable(filename_unc)
+     && (file_length(filename_err) == 0)) {
+    /* sucessfully uncompressed file */
+    gs->gs_filename_unc = filename_unc;
+  }
+  else {
+    /* report error */
+    g_snprintf(buf, 1024, _("Error while decompressing file %s:\n"),
+               gs->gs_filename);
+    ps_document_emit_error_msg(gs, buf);
+    if(file_length(filename_err) > 0) {
+      FILE *err;
+      if((err = fopen(filename_err, "r"))) {
+        /* print file to message window */
+        while(fgets(buf, 1024, err))
+          ps_document_emit_error_msg(gs, buf);
+        fclose(err);
+      }
+    }
+    unlink(filename_unc);
+    g_free(filename_unc);
+    filename_unc = NULL;
+  }
+  unlink(filename_err);
+  g_free(filename_err);
+  g_free(cmdline);
+  g_free(filename);
+  return filename_unc;
+}
+
+/*
+ * Check if gs->gs_filename or gs->gs_filename_unc is a pdf file and scan
+ * pdf file if necessary.
+ * Set gs->filename_dsc to the name of the dsc file or NULL.
+ * Error reporting via signal 'interpreter_message'.
+ */
+static gchar *
+check_pdf(PSDocument * gs)
+{
+  FILE *file;
+  gchar buf[1024], *filename;
+  int fd;
+
+  /* use uncompressed file as input if necessary */
+  filename = (gs->gs_filename_unc ? gs->gs_filename_unc : gs->gs_filename);
+
+  if((file = fopen(filename, "r"))
+     && (fread(buf, sizeof(char), 5, file) == 5)
+     && (strncmp(buf, "%PDF-", 5) == 0)) {
+    /* we found a PDF file */
+    gchar *fname, *filename_dsc, *filename_err, *cmd, *cmdline;
+    filename_dsc = g_strconcat(g_get_tmp_dir(), "/ggvXXXXXX", NULL);
+    if((fd = mkstemp(filename_dsc)) < 0) {
+      return NULL;
+    }
+    close(fd);
+    filename_err = g_strconcat(g_get_tmp_dir(), "/ggvXXXXXX", NULL);
+    if((fd = mkstemp(filename_err)) < 0) {
+      g_free(filename_dsc);
+      return NULL;
+    }
+    close(fd);
+    fname = g_shell_quote(filename);
+    cmd = g_strdup_printf(gtk_gs_defaults_get_dsc_cmd(), filename_dsc, fname);
+    g_free(fname);
+    /* this command (sometimes?) prints error messages to stdout! */
+    cmdline = g_strdup_printf("%s >%s 2>&1", cmd, filename_err);
+    g_free(cmd);
+
+    if((system(cmdline) == 0) && file_readable(filename_dsc)) {
+
+      /* success */
+      filename = gs->gs_filename_dsc = filename_dsc;
+
+      if(file_length(filename_err) > 0) {
+        gchar *err_msg = " ";
+        GtkWidget *dialog;
+        FILE *err;
+        GdkColor color;
+
+        if((err = fopen(filename_err, "r"))) {
+
+          /* print the content of the file to a message box */
+          while(fgets(buf, 1024, err))
+            err_msg = g_strconcat(err_msg, buf, NULL);
+
+          /* FIXME The dialog is not yet set to modal, difficult to 
+           * get the parent of the dialog box here 
+           */
+
+          dialog = gtk_message_dialog_new(NULL,
+                                          GTK_DIALOG_MODAL,
+                                          GTK_MESSAGE_WARNING,
+                                          GTK_BUTTONS_OK,
+                                          ("There was an error while scaning the file: %s \n%s"),
+                                          gs->gs_filename, err_msg);
+
+          gdk_color_parse("white", &color);
+          gtk_widget_modify_bg(GTK_WIDGET(dialog), GTK_STATE_NORMAL, &color);
+
+          g_signal_connect(G_OBJECT(dialog), "response",
+                           G_CALLBACK(gtk_widget_destroy), NULL);
+
+          gtk_window_set_resizable(GTK_WINDOW(dialog), FALSE);
+          gtk_widget_show(dialog);
+          g_free(err_msg);
+        }
+      }
+
+    }
+    else {
+      /* report error */
+      g_snprintf(buf, 1024,
+                 _("Error while converting pdf file %s:\n"), filename);
+      ps_document_emit_error_msg(gs, buf);
+
+      if(file_length(filename_err) > 0) {
+        FILE *err;
+        if((err = fopen(filename_err, "r"))) {
+          /* print file to message window */
+          while(fgets(buf, 1024, err))
+            ps_document_emit_error_msg(gs, buf);
+        }
+      }
+      unlink(filename_dsc);
+      g_free(filename_dsc);
+      filename = NULL;
+    }
+    unlink(filename_err);
+    g_free(filename_err);
+    g_free(cmdline);
+  }
+  if(NULL != file)
+    fclose(file);
+  return filename;
+}
+
+#ifdef BROKEN_XINERAMA_PATCH_THAT_SHOULD_NOT_BE_USED
+/* never mind this patch: a properly working X server should take care of
+   calculating the proper values. */
+static float
+compute_xdpi(void)
+{
+#   ifndef HAVE_XINERAMA
+  return 25.4 * gdk_screen_width() / gdk_screen_width_mm();
+#   else
+  Display *dpy;
+  dpy = (Display *) GDK_DISPLAY();
+  if(XineramaIsActive(dpy)) {
+    int num_heads;
+    XineramaScreenInfo *head_info;
+    head_info = (XineramaScreenInfo *) XineramaQueryScreens(dpy, &num_heads);
+    /* fake it with dimensions of the first head for now */
+    return 25.4 * head_info[0].width / gdk_screen_width_mm();
+  }
+  else {
+    return 25.4 * gdk_screen_width() / gdk_screen_width_mm();
+  }
+#   endif
+  /* HAVE_XINERAMA */
+}
+
+static float
+compute_ydpi(void)
+{
+#   ifndef HAVE_XINERAMA
+  return 25.4 * gdk_screen_height() / gdk_screen_height_mm();
+#   else
+  Display *dpy;
+  dpy = (Display *) GDK_DISPLAY();
+  if(XineramaIsActive(dpy)) {
+    int num_heads;
+    XineramaScreenInfo *head_info;
+    head_info = (XineramaScreenInfo *) XineramaQueryScreens(dpy, &num_heads);
+    /* fake it with dimensions of the first head for now */
+    return 25.4 * head_info[0].height / gdk_screen_height_mm();
+  }
+  else {
+    return 25.4 * gdk_screen_height() / gdk_screen_height_mm();
+  }
+#   endif
+  /* HAVE_XINERAMA */
+}
+#else
+static float
+compute_xdpi(void)
+{
+  return 25.4 * gdk_screen_width() / gdk_screen_width_mm();
+}
+
+static float
+compute_ydpi(void)
+{
+  return 25.4 * gdk_screen_height() / gdk_screen_height_mm();
+}
+#endif /* BROKEN_XINERAMA_PATCH_THAT_SHOULD_NOT_BE_USED */
+
+/* Compute new size of window, sets xdpi and ydpi if necessary.
+ * returns True if new window size is different */
+static gboolean
+compute_size(PSDocument * gs)
+{
+  guint new_width = 1;
+  guint new_height = 1;
+  gboolean change = FALSE;
+  gint orientation;
+
+  /* width and height can be changed, calculate window size according */
+  /* to xpdi and ydpi */
+  orientation = ps_document_get_orientation(gs);
+
+  switch (orientation) {
+  case GTK_GS_ORIENTATION_PORTRAIT:
+  case GTK_GS_ORIENTATION_UPSIDEDOWN:
+    new_width = (gs->urx - gs->llx) / 72.0 * gs->xdpi + 0.5;
+    new_height = (gs->ury - gs->lly) / 72.0 * gs->ydpi + 0.5;
+    break;
+  case GTK_GS_ORIENTATION_LANDSCAPE:
+  case GTK_GS_ORIENTATION_SEASCAPE:
+    new_width = (gs->ury - gs->lly) / 72.0 * gs->xdpi + 0.5;
+    new_height = (gs->urx - gs->llx) / 72.0 * gs->ydpi + 0.5;
+    break;
+  }
+
+  change = (new_width != gs->width * gs->zoom_factor)
+    || (new_height != gs->height * gs->zoom_factor);
+  gs->width = (gint) (new_width * gs->zoom_factor);
+  gs->height = (gint) (new_height * gs->zoom_factor);
+
+  return (change);
+}
+
+static gint
+ps_document_enable_interpreter(PSDocument * gs)
+{
+  g_return_val_if_fail(gs != NULL, FALSE);
+  g_return_val_if_fail(GTK_IS_GS(gs), FALSE);
+
+  if(!gs->gs_filename)
+    return 0;
+
+  gs->disable_start = FALSE;
+  
+  return start_interpreter(gs);
+}
+
+/* publicly accessible functions */
+
+GType
+ps_document_get_type(void)
+{
+  static GType gs_type = 0;
+  if(!gs_type) {
+    GTypeInfo gs_info = {
+      sizeof(PSDocumentClass),
+      (GBaseInitFunc) NULL,
+      (GBaseFinalizeFunc) NULL,
+      (GClassInitFunc) ps_document_class_init,
+      (GClassFinalizeFunc) NULL,
+      NULL,                     /* class_data */
+      sizeof(PSDocument),
+      0,                        /* n_preallocs */
+      (GInstanceInitFunc) ps_document_init
+    };
+
+    static const GInterfaceInfo document_info =
+    {
+        (GInterfaceInitFunc) ps_document_document_iface_init,
+        NULL,
+        NULL
+    };
+
+    gs_type = g_type_register_static(G_TYPE_OBJECT,
+                                     "PSDocument", &gs_info, 0);
+
+    g_type_add_interface_static (gs_type,
+                                 EV_TYPE_DOCUMENT,
+                                 &document_info);
+  }
+  return gs_type;
+
+
+}
+
+/*
+ * Show error message -> send signal "interpreter_message"
+ */
+static void
+ps_document_emit_error_msg(PSDocument * gs, const gchar * msg)
+{
+  gdk_pointer_ungrab(GDK_CURRENT_TIME);
+  if(strstr(msg, "Error:")) {
+    gs->gs_status = _("File is not a valid PostScript document.");
+    ps_document_cleanup(gs);
+  }
+}
+
+static gboolean
+document_load(PSDocument * gs, const gchar * fname)
+{
+  g_return_val_if_fail(gs != NULL, FALSE);
+  g_return_val_if_fail(GTK_IS_GS(gs), FALSE);
+
+  /* clean up previous document */
+  ps_document_cleanup(gs);
+
+  if(fname == NULL) {
+    gs->gs_status = "";
+    return FALSE;
+  }
+
+  /* prepare this document */
+
+  /* default values: no dsc information available  */
+  gs->structured_doc = FALSE;
+  gs->send_filename_to_gs = TRUE;
+  gs->current_page = -2;
+  gs->loaded = FALSE;
+  if(*fname == '/') {
+    /* an absolute path */
+    gs->gs_filename = g_strdup(fname);
+  }
+  else {
+    /* path relative to our cwd: make it absolute */
+    gchar *cwd = g_get_current_dir();
+    gs->gs_filename = g_strconcat(cwd, "/", fname, NULL);
+    g_free(cwd);
+  }
+
+  if((gs->reading_from_pipe = (strcmp(fname, "-") == 0))) {
+    gs->send_filename_to_gs = FALSE;
+  }
+  else {
+    /*
+     * We need to make sure that the file is loadable/exists!
+     * otherwise we want to exit without loading new stuff...
+     */
+    gchar *filename = NULL;
+
+    if(!file_readable(fname)) {
+      gchar buf[1024];
+      g_snprintf(buf, 1024, _("Cannot open file %s.\n"), fname);
+      ps_document_emit_error_msg(gs, buf);
+      gs->gs_status = _("File is not readable.");
+    }
+    else {
+      filename = check_filecompressed(gs);
+      if(filename)
+        filename = check_pdf(gs);
+    }
+
+    if(!filename || (gs->gs_psfile = fopen(filename, "r")) == NULL) {
+      ps_document_cleanup(gs);
+      return FALSE;
+    }
+
+    /* we grab the vital statistics!!! */
+    gs->doc = psscan(gs->gs_psfile, gs->respect_eof, filename);
+
+    if(gs->doc == NULL) {
+      /* File does not seem to be a Postscript one */
+      gchar buf[1024];
+      g_snprintf(buf, 1024, _("Error while scanning file %s\n"), fname);
+      ps_document_emit_error_msg(gs, buf);
+      ps_document_cleanup(gs);
+      gs->gs_status = _("The file is not a PostScript document.");
+      return FALSE;
+    }
+
+    if((!gs->doc->epsf && gs->doc->numpages > 0) ||
+       (gs->doc->epsf && gs->doc->numpages > 1)) {
+      gs->structured_doc = TRUE;
+      gs->send_filename_to_gs = FALSE;
+    }
+
+    /* We have to set up the orientation of the document */
+
+
+    /* orientation can only be portrait, and landscape or none.
+       This is the document default. A document can have
+       pages in landscape and some in portrait */
+    if(gs->override_orientation) {
+      /* If the orientation should be override... 
+         then gs->orientation has already the correct
+         value (it was set when the widget was created */
+      /* So do nothing */
+
+    }
+    else {
+      /* Otherwise, set the proper orientation for the doc */
+      gs->real_orientation = gs->doc->orientation;
+    }
+  }
+  ps_document_set_page_size(gs, -1, gs->current_page);
+  gs->loaded = TRUE;
+
+  gs->gs_status = _("Document loaded.");
+
+  return gs->loaded;
+}
+
+
+static gboolean
+ps_document_next_page(PSDocument * gs)
+{
+  XEvent event;
+
+  g_return_val_if_fail(gs != NULL, FALSE);
+  g_return_val_if_fail(GTK_IS_GS(gs), FALSE);
+
+  if(gs->interpreter_pid == 0) {    /* no interpreter active */
+    return FALSE;
+  }
+
+  if(gs->busy) {                /* interpreter is busy */
+    return FALSE;
+  }
+
+  gs->busy = TRUE;
+
+  event.xclient.type = ClientMessage;
+  event.xclient.display = gdk_display;
+  event.xclient.window = gs->message_window;
+  event.xclient.message_type = gdk_x11_atom_to_xatom(gs_class->next_atom);
+  event.xclient.format = 32;
+
+  gdk_error_trap_push();
+  XSendEvent(gdk_display, gs->message_window, FALSE, 0, &event);
+  gdk_flush();
+  gdk_error_trap_pop();
+
+  return TRUE;
+}
+
+static gint
+ps_document_get_current_page(PSDocument * gs)
+{
+  g_return_val_if_fail(gs != NULL, -1);
+  g_return_val_if_fail(GTK_IS_GS(gs), -1);
+
+  return gs->current_page;
+}
+
+static gint
+ps_document_get_page_count(PSDocument * gs)
+{
+  if(!gs->gs_filename)
+    return 0;
+
+  if(gs->doc) {
+    if(gs->structured_doc)
+      return gs->doc->numpages;
+    else
+      return G_MAXINT;
+  }
+  else
+    return 0;
+}
+
+static gboolean
+ps_document_goto_page(PSDocument * gs, gint page)
+{
+  g_return_val_if_fail(gs != NULL, FALSE);
+  g_return_val_if_fail(GTK_IS_GS(gs), FALSE);
+
+  if(!gs->gs_filename) {
+    return FALSE;
+  }
+
+  /* range checking... */
+  if(page < 0)
+    page = 0;
+
+  if(gs->structured_doc && gs->doc) {
+    if(page >= gs->doc->numpages)
+      page = gs->doc->numpages - 1;
+
+    if(page == gs->current_page && !gs->changed)
+      return TRUE;
+
+    gs->current_page = page;
+
+    if(gs->doc->pages[page].orientation != NONE &&
+       !gs->override_orientation &&
+       gs->doc->pages[page].orientation != gs->real_orientation) {
+      gs->real_orientation = gs->doc->pages[page].orientation;
+      gs->changed = TRUE;
+    }
+
+    ps_document_set_page_size(gs, -1, page);
+
+    gs->changed = FALSE;
+
+    if(is_interpreter_ready(gs)) {
+      ps_document_next_page(gs);
+    }
+    else {
+      ps_document_enable_interpreter(gs);
+      send_ps(gs, gs->doc->beginprolog, gs->doc->lenprolog, FALSE);
+      send_ps(gs, gs->doc->beginsetup, gs->doc->lensetup, FALSE);
+    }
+
+    send_ps(gs, gs->doc->pages[gs->current_page].begin,
+            gs->doc->pages[gs->current_page].len, FALSE);
+  }
+  else {
+    /* Unstructured document */
+    /* In the case of non structured documents,
+       GS read the PS from the  actual file (via command
+       line. Hence, ggv only send a signal next page.
+       If ghostview is not running it is usually because
+       the last page of the file was displayed. In that
+       case, ggv restarts GS again and the first page is displayed.
+     */
+    if(page == gs->current_page && !gs->changed)
+      return TRUE;
+
+    if(!is_interpreter_ready(gs))
+      ps_document_enable_interpreter(gs);
+
+    gs->current_page = page;
+
+    ps_document_next_page(gs);
+  }
+  return TRUE;
+}
+
+/*
+ * set pagesize sets the size from
+ * if new_pagesize is -1, then it is set to either
+ *  a) the default settings of pageid, if they exist, or if pageid != -1.
+ *  b) the default setting of the document, if it exists.
+ *  c) the default setting of the widget.
+ * otherwise, the new_pagesize is used as the pagesize
+ */
+static gboolean
+ps_document_set_page_size(PSDocument * gs, gint new_pagesize, gint pageid)
+{
+  gint new_llx = 0;
+  gint new_lly = 0;
+  gint new_urx = 0;
+  gint new_ury = 0;
+  GtkGSPaperSize *papersizes = gtk_gs_defaults_get_paper_sizes();
+
+  g_return_val_if_fail(gs != NULL, FALSE);
+  g_return_val_if_fail(GTK_IS_GS(gs), FALSE);
+
+  if(new_pagesize == -1) {
+    if(gs->default_size > 0)
+      new_pagesize = gs->default_size;
+    if(!gs->override_size && gs->doc) {
+      /* If we have a document:
+         We use -- the page size (if specified)
+         or the doc. size (if specified)
+         or the page bbox (if specified)
+         or the bounding box
+       */
+      if((pageid >= 0) && (gs->doc->numpages > pageid) &&
+         (gs->doc->pages) && (gs->doc->pages[pageid].size)) {
+        new_pagesize = gs->doc->pages[pageid].size - gs->doc->size;
+      }
+      else if(gs->doc->default_page_size != NULL) {
+        new_pagesize = gs->doc->default_page_size - gs->doc->size;
+      }
+      else if((pageid >= 0) &&
+              (gs->doc->numpages > pageid) &&
+              (gs->doc->pages) &&
+              (gs->doc->pages[pageid].boundingbox[URX] >
+               gs->doc->pages[pageid].boundingbox[LLX]) &&
+              (gs->doc->pages[pageid].boundingbox[URY] >
+               gs->doc->pages[pageid].boundingbox[LLY])) {
+        new_pagesize = -1;
+      }
+      else if((gs->doc->boundingbox[URX] > gs->doc->boundingbox[LLX]) &&
+              (gs->doc->boundingbox[URY] > gs->doc->boundingbox[LLY])) {
+        new_pagesize = -1;
+      }
+    }
+  }
+
+  /* Compute bounding box */
+  if(gs->doc && ((gs->doc->epsf && !gs->override_size) || new_pagesize == -1)) {    /* epsf or bbox */
+    if((pageid >= 0) &&
+       (gs->doc->pages) &&
+       (gs->doc->pages[pageid].boundingbox[URX] >
+        gs->doc->pages[pageid].boundingbox[LLX])
+       && (gs->doc->pages[pageid].boundingbox[URY] >
+           gs->doc->pages[pageid].boundingbox[LLY])) {
+      /* use page bbox */
+      new_llx = gs->doc->pages[pageid].boundingbox[LLX];
+      new_lly = gs->doc->pages[pageid].boundingbox[LLY];
+      new_urx = gs->doc->pages[pageid].boundingbox[URX];
+      new_ury = gs->doc->pages[pageid].boundingbox[URY];
+    }
+    else if((gs->doc->boundingbox[URX] > gs->doc->boundingbox[LLX]) &&
+            (gs->doc->boundingbox[URY] > gs->doc->boundingbox[LLY])) {
+      /* use doc bbox */
+      new_llx = gs->doc->boundingbox[LLX];
+      new_lly = gs->doc->boundingbox[LLY];
+      new_urx = gs->doc->boundingbox[URX];
+      new_ury = gs->doc->boundingbox[URY];
+    }
+  }
+  else {
+    if(new_pagesize < 0)
+      new_pagesize = gs->default_size;
+    new_llx = new_lly = 0;
+    if(gs->doc && !gs->override_size && gs->doc->size &&
+       (new_pagesize < gs->doc->numsizes)) {
+      new_urx = gs->doc->size[new_pagesize].width;
+      new_ury = gs->doc->size[new_pagesize].height;
+    }
+    else {
+      new_urx = papersizes[new_pagesize].width;
+      new_ury = papersizes[new_pagesize].height;
+    }
+  }
+
+  if(new_urx <= new_llx)
+    new_urx = papersizes[12].width;
+  if(new_ury <= new_lly)
+    new_ury = papersizes[12].height;
+
+  /* If bounding box changed, setup for new size. */
+  /* ps_document_disable_interpreter (gs); */
+  if((new_llx != gs->llx) || (new_lly != gs->lly) ||
+     (new_urx != gs->urx) || (new_ury != gs->ury)) {
+    gs->llx = new_llx;
+    gs->lly = new_lly;
+    gs->urx = new_urx;
+    gs->ury = new_ury;
+    gs->changed = TRUE;
+  }
+
+  if(gs->changed) {
+    set_up_page(gs);
+    return TRUE;
+  }
+
+  return FALSE;
+}
+
+static gfloat
+ps_document_zoom_to_fit(PSDocument * gs, gboolean fit_width)
+{
+  gint new_y;
+  gfloat new_zoom;
+  guint avail_w, avail_h;
+
+  g_return_val_if_fail(gs != NULL, 0.0);
+  g_return_val_if_fail(GTK_IS_GS(gs), 0.0);
+
+  avail_w = (gs->avail_w > 0) ? gs->avail_w : gs->width;
+  avail_h = (gs->avail_h > 0) ? gs->avail_h : gs->height;
+
+  new_zoom = ((gfloat) avail_w) / ((gfloat) gs->width) * gs->zoom_factor;
+  if(!fit_width) {
+    new_y = new_zoom * ((gfloat) gs->height) / gs->zoom_factor;
+    if(new_y > avail_h)
+      new_zoom = ((gfloat) avail_h) / ((gfloat) gs->height) * gs->zoom_factor;
+  }
+
+  return new_zoom;
+}
+
+static void
+ps_document_set_zoom(PSDocument * gs, gfloat zoom)
+{
+  g_return_if_fail(gs != NULL);
+  g_return_if_fail(GTK_IS_GS(gs));
+
+  switch (gs->zoom_mode) {
+  case GTK_GS_ZOOM_FIT_WIDTH:
+    zoom = ps_document_zoom_to_fit(gs, TRUE);
+    break;
+  case GTK_GS_ZOOM_FIT_PAGE:
+    zoom = ps_document_zoom_to_fit(gs, FALSE);
+    break;
+  case GTK_GS_ZOOM_ABSOLUTE:
+  default:
+    break;
+  }
+
+  if(fabs(gs->zoom_factor - zoom) > 0.001) {
+    gs->zoom_factor = zoom;
+    set_up_page(gs);
+    gs->changed = TRUE;
+  }
+
+  ps_document_goto_page(gs, gs->current_page);
+}
+
+static gboolean
+ps_document_load (EvDocument  *document,
+		  const char  *uri,
+		  GError     **error)
+{
+	gboolean result;
+	char *filename;
+
+	filename = g_filename_from_uri (uri, NULL, error);
+	if (!filename)
+		return FALSE;
+
+	result = document_load (PS_DOCUMENT (document), filename);
+
+	g_free (filename);
+
+	return result;
+}
+
+static int
+ps_document_get_n_pages (EvDocument  *document)
+{
+	return ps_document_get_page_count (PS_DOCUMENT (document));
+}
+
+static void
+ps_document_set_page (EvDocument  *document,
+		       int          page)
+{
+	ps_document_goto_page (PS_DOCUMENT (document), page);
+}
+
+static int
+ps_document_get_page (EvDocument  *document)
+{
+	return ps_document_get_current_page (PS_DOCUMENT (document));
+}
+
+static gboolean
+ps_document_widget_event (GtkWidget *widget, GdkEvent *event, gpointer data)
+{
+	PSDocument *gs = (PSDocument *) data;
+
+	if(event->type != GDK_CLIENT_EVENT)
+		return FALSE;
+
+	if (event->client.message_type == gs_class->page_atom) {
+		gs->busy = FALSE;
+		ev_document_changed (EV_DOCUMENT (gs));
+	}
+
+	return TRUE;
+}
+
+static void
+ps_document_set_target (EvDocument  *document,
+			GdkDrawable *target)
+{
+	PSDocument *gs = PS_DOCUMENT (document);
+	GtkWidget *widget;
+	gpointer data;
+
+	gs->pstarget = target;
+
+	if (gs->pstarget) {
+		gdk_window_get_user_data (gs->pstarget, &data);
+		g_return_if_fail (GTK_IS_WIDGET (data));
+
+		widget = GTK_WIDGET (data);
+		g_signal_connect (widget, "event",
+				  G_CALLBACK (ps_document_widget_event),
+				  document);
+	}
+
+	ps_document_goto_page (gs, gs->current_page);
+}
+
+static void
+ps_document_set_scale (EvDocument  *document,
+			double       scale)
+{
+	ps_document_set_zoom (PS_DOCUMENT (document), scale);
+}
+
+static void
+ps_document_set_page_offset (EvDocument  *document,
+			      int          x,
+			      int          y)
+{
+}
+
+static void
+ps_document_get_page_size (EvDocument   *document,
+			    int          *width,
+			    int          *height)
+{
+	PSDocument *gs = PS_DOCUMENT (document);
+
+	if (width) {
+		*width = gs->width;
+	}
+
+	if (height) {
+		*height = gs->height;
+	}
+}
+
+static void
+ps_document_render (EvDocument  *document,
+		    int          clip_x,
+		    int          clip_y,
+		    int          clip_width,
+		    int          clip_height)
+{
+	PSDocument *gs = PS_DOCUMENT (document);
+	GdkGC *gc;
+
+	if (gs->pstarget == NULL ||
+	    gs->bpixmap == NULL) {
+		return;
+	}
+
+	gc = gdk_gc_new (gs->pstarget);
+
+	gdk_draw_drawable (gs->pstarget, gc,
+			   gs->bpixmap,
+			   clip_x, clip_y,
+			   clip_x, clip_y,
+			   clip_width, clip_height);
+
+	g_object_unref (gc);
+}
+
+static void
+ps_document_document_iface_init (EvDocumentIface *iface)
+{
+	iface->load = ps_document_load;
+	iface->get_n_pages = ps_document_get_n_pages;
+	iface->set_page = ps_document_set_page;
+	iface->get_page = ps_document_get_page;
+	iface->set_scale = ps_document_set_scale;
+	iface->set_target = ps_document_set_target;
+	iface->set_page_offset = ps_document_set_page_offset;
+	iface->get_page_size = ps_document_get_page_size;
+	iface->render = ps_document_render;
+}