ROX-Filer/src/remote.c

   1 /*
   2  * $Id$
   3  *
   4  * ROX-Filer, filer for the ROX desktop project
   5  * Copyright (C) 2000, Thomas Leonard, <tal197@ecs.soton.ac.uk>.
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the Free
   9  * Software Foundation; either version 2 of the License, or (at your option)
  10  * any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful, but WITHOUT
  13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  15  * more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along with
  18  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  19  * Place, Suite 330, Boston, MA  02111-1307  USA
  20  */
  21
  22 /* This code is used to communicate between two copies of the filer:
  23  * If the filer is run and the same version of the filer is already
  24  * running on the same machine then the new copy simply asks the old
  25  * one deal with it and quits.
  26  */
  27
  28 #include "config.h"
  29
  30 #include <gdk/gdkx.h>
  31 #include <X11/X.h>
  32 #include <X11/Xatom.h>
  33 #include <gtk/gtk.h>
  34 #include <gtk/gtkinvisible.h>
  35
  36 #include "main.h"
  37 #include "support.h"
  38 #include "filer.h"
  39 #include "gui_support.h"
  40
  41 static GdkAtom filer_atom;      /* _ROX_FILER_VERSION_HOST */
  42 static GdkAtom ipc_atom;        /* _ROX_FILER_OPEN */
  43
  44 /* Static prototypes */
  45 static GdkWindow *get_existing_ipc_window();
  46 static gboolean get_ipc_property(GdkWindow *window, Window *r_xid);
  47 static gboolean ipc_prop_changed(GtkWidget *window,
  48                                  GdkEventProperty *event,
  49                                  gpointer data);
  50 static void send_request(GdkWindow *ipc_window, int argc, char **argv);
  51 static void open_dirs(guchar *data, int length);
  52
  53 /****************************************************************
  54  *                      EXTERNAL INTERFACE                      *
  55  ****************************************************************/
  56
  57
  58 /* Try to get an already-running filer to handle things (only if
  59  * new_copy is FALSE); TRUE if we succeed.
  60  * Create and IPC widget so that future filers can contact us.
  61  */
  62 gboolean remote_init(int argc, char **argv, gboolean new_copy)
  63 {
  64         guchar  *unique_id;
  65         GdkWindowPrivate        *window;
  66         GdkWindow               *existing_ipc_window;
  67         GtkWidget               *ipc_window;
  68
  69         unique_id = g_strdup_printf("_ROX_FILER_%s_%s",
  70                                 VERSION, our_host_name());
  71         filer_atom = gdk_atom_intern(unique_id, FALSE);
  72         g_free(unique_id);
  73
  74         ipc_atom = gdk_atom_intern("_ROX_FILER_OPEN", FALSE);
  75
  76         existing_ipc_window = new_copy ? NULL : get_existing_ipc_window();
  77         if (existing_ipc_window)
  78         {
  79                 send_request(existing_ipc_window, argc, argv);
  80                 return TRUE;
  81         }
  82
  83         /* Note: possible race-condition here if two filers both
  84          * start at the same time and one isn't already running.
  85          * Oh well.
  86          */
  87
  88         ipc_window = gtk_invisible_new();
  89         gtk_widget_realize(ipc_window);
  90
  91         window = (GdkWindowPrivate *) ipc_window->window;
  92
  93         /* Make the IPC window contain a property pointing to
  94          * itself - this can then be used to check that it really
  95          * is an IPC window.
  96          */
  97         gdk_property_change(ipc_window->window, filer_atom,
  98                         XA_WINDOW, 32, GDK_PROP_MODE_REPLACE,
  99                         (guchar *) &window->xwindow, 1);
 100
 101         /* Get notified when the IPC property is changed */
 102         gtk_widget_add_events(ipc_window, GDK_PROPERTY_CHANGE_MASK);
 103         gtk_signal_connect(GTK_OBJECT(ipc_window), "property-notify-event",
 104                         GTK_SIGNAL_FUNC(ipc_prop_changed), NULL);
 105
 106         /* Make the root window contain a pointer to the IPC window */
 107         gdk_property_change(GDK_ROOT_PARENT(), filer_atom,
 108                         XA_WINDOW, 32, GDK_PROP_MODE_REPLACE,
 109                         (guchar *) &window->xwindow, 1);
 110
 111         return FALSE;
 112 }
 113
 114
 115 /****************************************************************
 116  *                      INTERNAL FUNCTIONS                      *
 117  ****************************************************************/
 118
 119 /* Get the remote IPC window of the already-running filer if there
 120  * is one.
 121  */
 122 static GdkWindow *get_existing_ipc_window()
 123 {
 124         Window          xid, xid_confirm;
 125         GdkWindow       *window;
 126
 127         if (!get_ipc_property(GDK_ROOT_PARENT(), &xid))
 128                 return NULL;
 129
 130         window = gdk_window_foreign_new(xid);
 131         if (!window)
 132                 return NULL;
 133
 134         if (!get_ipc_property(window, &xid_confirm) || xid_confirm != xid)
 135                 return NULL;
 136
 137         return window;
 138 }
 139
 140 /* Returns the 'rox_atom' property of 'window' */
 141 static gboolean get_ipc_property(GdkWindow *window, Window *r_xid)
 142 {
 143         guchar          *data;
 144         gint            format, length;
 145         gboolean        retval = FALSE;
 146
 147         if (gdk_property_get(window, filer_atom, XA_WINDOW, 0, 4,
 148                         FALSE, NULL, &format, &length, &data) && data)
 149         {
 150                 if (format == 32 && length == 4)
 151                 {
 152                         retval = TRUE;
 153                         *r_xid = *((Window *) data);
 154                 }
 155                 g_free(data);
 156         }
 157
 158         return retval;
 159 }
 160
 161
 162 static gboolean ipc_prop_changed(GtkWidget *window,
 163                                  GdkEventProperty *event,
 164                                  gpointer data)
 165 {
 166         if (event->atom == ipc_atom)
 167         {
 168                 gint    grab_len = 4096;
 169                 gint    length;
 170                 guchar  *data;
 171
 172                 while (1)
 173                 {
 174
 175                         if (!gdk_property_get(window->window, ipc_atom,
 176                                         XA_STRING, 0, grab_len,
 177                                         TRUE, NULL, NULL,
 178                                         &length, &data) && data)
 179                                 return TRUE;    /* Error? */
 180
 181                         if (length >= grab_len)
 182                         {
 183                                 /* Didn't get all of it - try again */
 184                                 grab_len <<= 1;
 185                                 g_free(data);
 186                                 continue;
 187                         }
 188
 189                         data = g_realloc(data, length + 1);
 190                         data[length] = '\0';
 191
 192                         open_dirs(data, length);
 193
 194                         g_free(data);
 195                         break;
 196                 }
 197
 198                 return TRUE;
 199         }
 200
 201         return FALSE;
 202 }
 203
 204 static void send_request(GdkWindow *ipc_window, int argc, char **argv)
 205 {
 206         char    *data, *d;
 207         int     i, size = 0;
 208
 209         if (argc == 0)
 210         {
 211                 argc = 1;
 212                 argv = &home_dir;
 213         }
 214
 215         for (i = 0; i < argc; i++)
 216                 size += strlen(argv[i]) + 1;
 217
 218         data = g_malloc(size);
 219
 220         d = data;
 221         for (i = 0; i < argc; i++)
 222         {
 223                 int     len;
 224
 225                 len = strlen(argv[i]);
 226                 memcpy(d, argv[i], len + 1);
 227                 d += len + 1;
 228         }
 229
 230         gdk_property_change(ipc_window, ipc_atom, XA_STRING, 8,
 231                         GDK_PROP_MODE_APPEND, data, size);
 232
 233         g_free(data);
 234 }
 235
 236 /* data is a sequence of nul-term'd strings */
 237 static void open_dirs(guchar *data, int length)
 238 {
 239         while (length > 0)
 240         {
 241                 int     len;
 242
 243                 if (*data)
 244                         filer_opendir(data, PANEL_NO);
 245
 246                 len = strlen(data) + 1;
 247                 data += len;
 248                 length -= len;
 249         }
 250 }