path: root/x11/gnomesession/files/patch-dbus

--- gnome-session/main.c.orig   Tue Mar 21 12:37:40 2006
+++ gnome-session/main.c    Sun Apr 23 23:05:38 2006
@@ -43,6 +43,7 @@
 #include "command.h"
 #include "splash-widget.h"
 #include "util.h"
+#include "gsm-dbus.h"
 #include "gsm-sound.h"
 #include "gsm-gsd.h"
 #include "gsm-keyring.h"
@@ -334,6 +335,7 @@ main (int argc, char *argv[])
   char *display_str;
   char **versions;
   GConfClient *gconf_client;
+  gboolean dbus_daemon_owner;
   
   if (getenv ("GSM_VERBOSE_DEBUG"))
     gsm_set_verbose (TRUE);
@@ -415,6 +417,7 @@ main (int argc, char *argv[])
   fprintf (stderr, "SESSION_MANAGER=%s\n", getenv ("SESSION_MANAGER"));
   gnome_window_icon_set_default_from_file (GNOME_ICONDIR"/gnome-session.png");
 
+  dbus_daemon_owner = gsm_dbus_daemon_start ();
 
   /* Make sure children see the right value for DISPLAY.  This is
      useful if --display was specified on the command line.  */
@@ -495,6 +498,9 @@ main (int argc, char *argv[])
   gsm_sound_logout ();
 
   gsm_keyring_daemon_stop ();
+
+  if (dbus_daemon_owner)
+    gsm_dbus_daemon_stop ();
 
   g_object_unref (gconf_client);
   gsm_shutdown_gconfd ();
--- gnome-session/gsm-dbus.h.orig   Sun Apr 23 23:01:47 2006
+++ gnome-session/gsm-dbus.h    Sun Apr 23 23:00:53 2006
@@ -0,0 +1,27 @@
+/* gsm-dbus.h - Handle the dbus-daemon process.
+ *
+ * Copyright (c) 2006 Julio M. Merino Vidal <jmmv@NetBSD.org>
+ *
+ * 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, 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.
+ */
+
+#ifndef GSM_DBUS_H
+#define GSM_DBUS_H
+
+gboolean gsm_dbus_daemon_start (void);
+void     gsm_dbus_daemon_stop (void);
+
+#endif /* GSM_DBUS_H */
--- gnome-session/gsm-dbus.c.orig   Sun Apr 23 23:09:40 2006
+++ gnome-session/gsm-dbus.c    Sun Apr 23 23:10:21 2006
@@ -0,0 +1,360 @@
+/* gsm-dbus.c - Handle the dbus-daemon process.
+ *
+ * Copyright (c) 2006 Julio M. Merino Vidal <jmmv@NetBSD.org>
+ *
+ * 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, 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.
+ */
+
+#if HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <sys/wait.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include <glib.h>
+#include <glib/gprintf.h>
+
+#include "gsm-dbus.h"
+
+static pid_t    dbus_daemon_pid = 0;
+
+static gboolean have_dbus_daemon (void);
+static gboolean have_running_instance (void);
+static int      read_line (int, char *, ssize_t);
+static void     start_child (int, int);
+static void     start_parent (int, int, pid_t);
+
+/* ---------------------------------------------------------------------
+ * PUBLIC INTERFACE
+ * --------------------------------------------------------------------- */
+
+/*
+ * Starts the dbus-daemon if not already running and attaches it to the
+ * current environment by defining DBUS_SESSION_BUS_ADDRESS.  Returns
+ * true if we launch a new dbus-daemon so that we know if we have to call
+ * gsm_dbus_daemon_stop later on or not.
+ *
+ * This function can only be called if dbus-daemon is not already running
+ * (i.e., if gnome-session is starting up or if gsm_dbus_daemon_stop was
+ * previously called).
+ */
+gboolean
+gsm_dbus_daemon_start (void)
+{
+  int address_pipe[2];
+  int pid_pipe[2];
+  pid_t tmp_pid;
+
+  g_assert (dbus_daemon_pid == 0);
+
+  if (have_running_instance ())
+    return FALSE;
+  if (! have_dbus_daemon ())
+    return FALSE;
+
+  /*
+   * At this point, dbus-daemon is not running for the current session
+   * and the binary exists.  Spawn it.
+   */
+
+  if (pipe (address_pipe) == -1)
+    {
+      g_printerr ("Cannot create address pipe for dbus-daemon\n");
+      return FALSE;
+    }
+
+  if (pipe (pid_pipe) == -1)
+    {
+      close (address_pipe[0]);
+      close (address_pipe[1]);
+      g_printerr ("Cannot create pid pipe for dbus-daemon\n");
+      return FALSE;
+    }
+
+  tmp_pid = fork ();
+  if (tmp_pid == -1)
+    {
+      close (address_pipe[0]);
+      close (address_pipe[1]);
+      close (pid_pipe[0]);
+      close (pid_pipe[1]);
+      g_printerr ("Cannot create child process for dbus-daemon\n");
+      return FALSE;
+    }
+  else if (tmp_pid == 0)
+    {
+      close (address_pipe[0]);
+      close (pid_pipe[0]);
+      start_child (address_pipe[1], pid_pipe[1]);
+      /* NOTREACHED */
+    }
+  else
+    {
+      close (address_pipe[1]);
+      close (pid_pipe[1]);
+      start_parent (address_pipe[0], pid_pipe[0], tmp_pid);
+    }
+
+  g_assert (dbus_daemon_pid != 0);
+  return TRUE;
+}
+
+/*
+ * Stops the running dbus-daemon.  Can only be called if we own the process;
+ * i.e., if gsm_dbus_daemon_start returned true.
+ */
+void
+gsm_dbus_daemon_stop (void)
+{
+  g_assert (dbus_daemon_pid != 0);
+
+  if (kill (dbus_daemon_pid, SIGTERM) == -1)
+    g_printerr ("Failed to kill dbus-daemon (pid %d)\n",
+                dbus_daemon_pid);
+  else
+    {
+      dbus_daemon_pid = 0;
+      g_unsetenv ("DBUS_SESSION_BUS_ADDRESS");
+    }
+}
+
+/* ---------------------------------------------------------------------
+ * PRIVATE FUNCTIONS
+ * --------------------------------------------------------------------- */
+
+/*
+ * Check whether the dbus-daemon binary is in the path and raise an
+ * appropriate error message if it is not.
+ */
+static gboolean
+have_dbus_daemon (void)
+{
+  gboolean result;
+  gchar *file_name;
+
+  file_name = g_find_program_in_path ("dbus-daemon");
+  if (file_name == NULL)
+    g_printerr ("Cannot locate dbus-daemon\n");
+  result = file_name != NULL;
+  g_free (file_name);
+
+  return result;
+}
+
+/*
+ * Check whether there is a dbus-daemon session instance currently running
+ * (not spawned by us).  If there is, do nothing and return TRUE.
+ */
+static gboolean
+have_running_instance (void)
+{
+  const gchar *address_str;
+
+  g_assert (dbus_daemon_pid == 0);
+
+  address_str = g_getenv ("DBUS_SESSION_BUS_ADDRESS");
+  return address_str != NULL;
+}
+
+/*
+ * Reads a single line from the given file descriptor and stores it in the
+ * buffer pointed to by 'buf'.
+ *
+ * After finding the first new line character, the function returns.  This
+ * is to avoid reading dbus' pid multiple times from its file descriptor.
+ */
+static int
+read_line (int fd, char *buf, ssize_t bufsize)
+{
+  gboolean discard, done;
+  ssize_t bytes;
+
+  bytes = 0;
+  discard = FALSE;
+  done = FALSE;
+  do
+    {
+      ssize_t i, result;
+
+      result = read (fd, &buf[bytes], bufsize - bytes);
+      if (result < 0)
+        return -1;
+      else if (result > 0 && !discard)
+        {
+          if (bytes + result < bufsize)
+            bytes += result;
+          else
+            bytes = bufsize - 1;
+        }
+      else
+        done = TRUE;
+
+      for (i = 0; !discard && i < bytes; i++)
+        if (buf[i] == '\n')
+          {
+            buf[i] = '\0';
+            discard = TRUE;
+          }
+    }
+  while (!done);
+
+  g_assert (bytes >= 0 && bytes < bufsize);
+  buf[bytes] = '\0';
+
+  return bytes;
+}
+
+/*
+ * Code run by the child process after the fork to launch dbus-demon.
+ *
+ * As the child, this execs dbus-daemon, connecting it to the appropriate
+ * file descriptors.
+ */
+static void
+start_child (int address_fd, int pid_fd)
+{
+  gchar address_str[16];
+  gchar pid_str[16];
+  int fd;
+  long open_max;
+
+  open_max = sysconf (_SC_OPEN_MAX);
+  for (fd = 0; fd < open_max; fd++)
+    {
+      if (fd != STDIN_FILENO && fd != STDOUT_FILENO && fd != STDERR_FILENO &&
+          fd != address_fd && fd != pid_fd)
+        fcntl (fd, F_SETFD, FD_CLOEXEC);
+    }
+
+  g_snprintf (address_str, sizeof (address_str), "%d", address_fd);
+  g_snprintf (pid_str, sizeof (pid_str), "%d", pid_fd);
+
+  execlp ("dbus-daemon",
+          "dbus-daemon",
+          "--fork",
+          "--print-address", address_str,
+          "--print-pid", pid_str,
+          "--session",
+          NULL);
+
+  g_printerr ("Could not launch dbus-daemon\n");
+
+  exit (EXIT_FAILURE);
+}
+
+/*
+ * Code run by the parent process after the fork to launch dbus-demon.
+ *
+ * As the parent, this waits until dbus-daemon forks itself again and
+ * fetches its address and pid to later take its ownership.
+ */
+static void
+start_parent (int address_fd, int pid_fd, pid_t child)
+{
+  char address_str[256];
+  char pid_str[256];
+  char *tmp_ep;
+  int exitstat;
+  unsigned long tmp_num;
+  ssize_t bytes;
+
+  g_assert (child > 0);
+
+  /*
+   * dbus-daemon --fork causes our child process to exit prematurely
+   * because it is not the real daemon.  See if it worked correctly
+   * and clean it up to avoid a zombie.
+   *
+   * Life could be much easier if dbus-daemon had a --no-fork flag.
+   * But, as it hasn't it, we cannot assume that it will not fork,
+   * because we have no control over its configuration file.
+   */
+  if (waitpid (child, &exitstat, 0) == -1)
+    {
+      close (address_fd);
+      close (pid_fd);
+
+      g_printerr ("Failed to get dbus-daemon status\n");
+      return;
+    }
+  if (!WIFEXITED (exitstat) || WEXITSTATUS (exitstat) != EXIT_SUCCESS)
+    {
+      close (address_fd);
+      close (pid_fd);
+
+      g_printerr ("dbus-daemon exited unexpectedly\n");
+      return;
+    }
+
+  /*
+   * Fetch dbus-daemon address.
+   */
+  bytes = read_line (address_fd, address_str, sizeof (address_str));
+  if (bytes == -1 || bytes == 0)
+    {
+      close (address_fd);
+      close (pid_fd);
+
+      g_printerr ("Failed to get dbus-daemon's address\n");
+      return;
+    }
+
+  /*
+   * Fetch dbus-daemon pid.
+   */
+  bytes = read_line (pid_fd, pid_str, sizeof (pid_str));
+  if (bytes == -1 || bytes == 0)
+    {
+      close (address_fd);
+      close (pid_fd);
+
+      g_printerr ("Failed to get dbus-daemon's pid\n");
+      return;
+    }
+
+  close (address_fd);
+  close (pid_fd);
+
+  /*
+   * Convert the string printed in pid_fd to a pid value.  Do the usual
+   * strtoul dance to check for a valid number.
+   */
+  errno = 0;
+  tmp_num = strtoul(pid_str, &tmp_ep, 10);
+  if (pid_str[0] == '\0' || *tmp_ep != '\0')
+    {
+      g_printerr ("dbus-daemon pid invalid (not a number)\n");
+      return;
+    }
+  if (errno == ERANGE && tmp_num == ULONG_MAX)
+    {
+      g_printerr ("dbus-daemon pid invalid (out of range)\n");
+      return;
+    }
+  dbus_daemon_pid = tmp_num;
+
+  /*
+   * All right!  Tell our future children about the new born dbus-daemon.
+   */
+  g_setenv ("DBUS_SESSION_BUS_ADDRESS", address_str, TRUE);
+}