Use fewer global variables. Separate monolithic gdm.h into component

2007-04-02  William Jon McCann  <mccann@jhu.edu>

	* common/Makefile.am:
	* common/gdm-common.c: (v4_v4_equal), (v6_v6_equal),
	(gdm_address_equal), (gdm_address_is_loopback),
	(gdm_address_get_info):
	* common/gdm-common.h:
	* common/gdm-config.c: (gdm_config_peek_value),
	(gdm_config_get_value), (gdm_config_peek_value_for_id),
	(gdm_config_peek_string_for_id), (gdm_config_get_string_for_id),
	(gdm_config_get_int_for_id), (gdm_config_set_int_for_id):
	* common/gdm-config.h:
	* common/gdm-log.c: (log_level_to_priority_and_prefix),
	(gdm_log_default_handler), (gdm_log_set_debug), (gdm_log_init),
	(gdm_log_shutdown):
	* common/gdm-log.h:
	* configure.ac:
	* daemon/Makefile.am:
	* daemon/auth.c: (add_auth_entry), (add_auth_entry_for_addr),
	(get_local_auths), (gdm_auth_user_add), (gdm_auth_set_local_auth),
	(gdm_auth_free_auth_list):
	* daemon/choose.c: (get_first_address_for_node), (gdm_choose_data),
	(gdm_choose_indirect_alloc),
	(gdm_choose_indirect_dispose_empty_id),
	(gdm_choose_indirect_lookup_by_chosen),
	(gdm_choose_indirect_lookup), (gdm_choose_indirect_dispose):
	* daemon/choose.h:
	* daemon/cookie.c:
	* daemon/cookie.h:
	* daemon/display.c: (gdm_display_manage), (count_session_limits),
	(gdm_display_dispose), (gdm_display_lookup):
	* daemon/display.h:
	* daemon/errorgui.c: (setup_dialog), (gdm_errorgui_error_box_full),
	(gdm_errorgui_error_box), (gdm_errorgui_failsafe_question),
	(gdm_errorgui_failsafe_yesno), (gdm_errorgui_failsafe_ask_buttons):
	* daemon/errorgui.h:
	* daemon/filecheck.c: (gdm_file_check), (gdm_auth_file_check):
	* daemon/gdm-daemon-config.c: (gdm_daemon_config_get_display_list),
	(gdm_daemon_config_display_list_append),
	(gdm_daemon_config_display_list_insert),
	(gdm_daemon_config_display_list_remove),
	(gdm_daemon_config_get_bool_for_id),
	(gdm_daemon_config_get_int_for_id),
	(gdm_daemon_config_get_string_for_id), (handle_no_displays),
	(gdm_daemon_config_parse):
	* daemon/gdm-daemon-config.h:
	* daemon/gdm-net.c:
	* daemon/gdm-net.h:
	* daemon/gdm.c: (mark_display_exists), (gdm_daemonify),
	(gdm_start_first_unborn_local), (gdm_final_cleanup),
	(deal_with_x_crashes), (gdm_safe_restart), (gdm_try_logout_action),
	(main), (order_exists), (get_new_order), (gdm_handle_message),
	(find_display), (handle_flexi_server), (handle_dynamic_server),
	(gdm_handle_user_message):
	* daemon/gdm.h:
	* daemon/gdmconsolekit.c: (get_path_array_from_iter):
	* daemon/gdmconsolekit.h:
	* daemon/md5.h:
	* daemon/misc.c: (gdm_clearenv_no_lang), (gdm_get_free_display),
	(gdm_exec_wait), (gdm_fork_extra), (gdm_wait_for_extra),
	(gdm_address_peek_local_list), (gdm_address_is_local),
	(fillout_addrinfo), (gdm_gethostbyname), (gdm_gethostbyaddr),
	(gdm_hostent_copy):
	* daemon/misc.h:
	* daemon/server.c: (gdm_exec_fbconsole), (gdm_server_spawn):
	* daemon/server.h:
	* daemon/slave.c: (get_runlevel), (gdm_slave_start),
	(focus_first_x_window), (run_config), (play_login_sound),
	(gdm_slave_greeter), (send_chosen_host), (gdm_slave_chooser),
	(session_child_run), (gdm_slave_session_start),
	(gdm_slave_session_stop), (check_for_interruption),
	(gdm_child_exit), (gdm_slave_exec_script),
	(gdm_parse_enriched_login), (gdm_is_user_valid):
	* daemon/slave.h:
	* daemon/verify-crypt.c: (gdm_verify_user),
	(gdm_verify_setup_user):
	* daemon/verify-pam.c: (gdm_verify_pam_conv),
	(gdm_verify_standalone_pam_conv), (gdm_verify_user),
	(gdm_verify_setup_user), (gdm_verify_cleanup), (gdm_verify_check):
	* daemon/verify-shadow.c: (gdm_verify_user),
	(gdm_verify_setup_user):
	* daemon/verify.h:
	* daemon/xdmcp.c: (gdm_xdmcp_displays_from_host),
	(gdm_xdmcp_display_lookup_by_host), (ai_family_str), (ai_type_str),
	(ai_protocol_str), (ai_flags_str), (debug_addrinfo),
	(gdm_xdmcp_create_socket), (gdm_xdmcp_bind), (gdm_xdmcp_init),
	(gdm_xdmcp_run), (gdm_xdmcp_close), (gdm_xdmcp_decode_packet),
	(gdm_xdmcp_handle_query), (set_port_for_request),
	(set_address_for_request), (gdm_xdmcp_send_forward_query),
	(gdm_forward_query_alloc), (gdm_forward_query_lookup),
	(gdm_forward_query_dispose), (create_sa_from_request),
	(gdm_xdmcp_handle_forward_query), (gdm_xdmcp_send_willing),
	(gdm_xdmcp_send_unwilling),
	(gdm_xdmcp_really_send_managed_forward), (managed_forward_handler),
	(gdm_xdmcp_send_managed_forward),
	(gdm_xdmcp_send_got_managed_forward), (gdm_xdmcp_handle_request),
	(gdm_xdmcp_send_accept), (gdm_xdmcp_send_decline),
	(gdm_xdmcp_handle_manage), (gdm_xdmcp_handle_managed_forward),
	(gdm_xdmcp_whack_queued_managed_forwards),
	(gdm_xdmcp_handle_got_managed_forward), (gdm_xdmcp_send_refuse),
	(gdm_xdmcp_send_failed), (gdm_xdmcp_handle_keepalive),
	(gdm_xdmcp_send_alive), (gdm_xdmcp_host_allow),
	(gdm_xdmcp_display_alloc), (gdm_xdmcp_display_lookup),
	(gdm_xdmcp_display_dispose_check), (gdm_xdmcp_displays_check),
	(gdm_xdmcp_recount_sessions):
	* daemon/xdmcp.h:
	* gui/Makefile.am:
	* gui/gdmXnestchooser.c:
	* gui/gdmchooser.c: (gdm_chooser_host_alloc), (gdm_chooser_cancel),
	(gdm_chooser_manage), (gdm_read_config), (gdm_reread_config),
	(main):
	* gui/gdmcomm.c: (do_command), (gdmcomm_call_gdm_real):
	* gui/gdmcommon.c: (gdm_common_log_init),
	(gdm_common_log_set_debug), (gdm_common_fail_exit),
	(gdm_common_fail_greeter), (gdm_common_info), (gdm_common_error),
	(gdm_common_warning), (gdm_common_debug), (gdm_common_expand_text):
	* gui/gdmcommon.h:
	* gui/gdmconfig.c:
	* gui/gdmdynamic.c: (main):
	* gui/gdmflexiserver.c: (main):
	* gui/gdmlanguages.c:
	* gui/gdmlogin.c: (gdm_login_restart_handler),
	(gdm_login_halt_handler), (gdm_login_use_chooser_handler),
	(gdm_read_config), (gdm_reread_config), (main):
	* gui/gdmsession.c:
	* gui/gdmsetup.c:
	* gui/gdmuser.c:
	* gui/gdmwm.c:
	* gui/greeter/greeter.c: (gdm_read_config),
	(greeter_reread_config), (main):
	* gui/greeter/greeter_item_customlist.c:
	* gui/greeter/greeter_item_pam.c:
	* gui/greeter/greeter_item_timed.c:
	* gui/greeter/greeter_item_ulist.c:
	* gui/greeter/greeter_parser.c: (parse_show):
	* gui/greeter/greeter_system.c: (query_greeter_restart_handler),
	(query_greeter_halt_handler), (greeter_restart_handler),
	(greeter_halt_handler), (greeter_chooser_handler):

	Use fewer global variables.
	Separate monolithic gdm.h into component parts.
	Use the Glib message logging API to write to syslog.
	Cleans up the ipv4/6 handling in the daemon to use a common code
	patch and be mostly AF- independent.
	Add a few convenience functions to gdm-config for get/set by ID.
	Patch from bug #376010


svn path=/trunk/; revision=4762

7 files changed, 469 insertions, 18 deletions

diff --git a/common/Makefile.am b/common/Makefile.am
index a67468c1..d55fff78 100644
--- a/common/Makefile.am
+++ b/common/Makefile.am
@@ -34,12 +34,15 @@ libgdmcommon_a_SOURCES =	\
 	gdm-common-config.c	\
 	gdm-config.h		\
 	gdm-config.c		\
+	gdm-log.h		\
+	gdm-log.c		\
 	ve-signal.h		\
 	ve-signal.c		\
 	$(NULL)
 
 noinst_PROGRAMS = 		\
 	test-config		\
+	test-log		\
 	$(NULL)
 
 test_config_SOURCES = 		\
@@ -51,3 +54,12 @@ test_config_LDADD =		\
 	$(top_builddir)/common/libgdmcommon.a	\
 	$(GLIB_LIBS)		\
 	$(NULL)
+
+test_log_SOURCES = 		\
+	test-log.c	 	\
+	$(NULL)
+
+test_log_LDADD =		\
+	$(top_builddir)/common/libgdmcommon.a	\
+	$(GLIB_LIBS)		\
+	$(NULL)
diff --git a/common/gdm-common.c b/common/gdm-common.c
index 30c93ca7..dbb3ff31 100644
--- a/common/gdm-common.c
+++ b/common/gdm-common.c
@@ -32,6 +32,93 @@
 
 #include "gdm-common.h"
 
+static gboolean
+v4_v4_equal (const struct sockaddr_in *a,
+	     const struct sockaddr_in *b)
+{
+	return a->sin_addr.s_addr == b->sin_addr.s_addr;
+}
+
+#ifdef ENABLE_IPV6
+static gboolean
+v6_v6_equal (struct sockaddr_in6 *a,
+	     struct sockaddr_in6 *b)
+{
+	return IN6_ARE_ADDR_EQUAL (&a->sin6_addr, &b->sin6_addr);
+}
+#endif
+
+#define SA(__s)	   ((struct sockaddr *) __s)
+#define SIN(__s)   ((struct sockaddr_in *) __s)
+#define SIN6(__s)  ((struct sockaddr_in6 *) __s)
+
+gboolean
+gdm_address_equal (struct sockaddr_storage *sa,
+		   struct sockaddr_storage *sb)
+{
+	guint8 fam_a;
+       	guint8 fam_b;
+
+	g_return_val_if_fail (sa != NULL, FALSE);
+	g_return_val_if_fail (sb != NULL, FALSE);
+
+	fam_a = sa->ss_family;
+	fam_b = sb->ss_family;
+
+	if (fam_a == AF_INET && fam_b == AF_INET) {
+		return v4_v4_equal (SIN (sa), SIN (sb));
+	}
+#ifdef ENABLE_IPV6
+	else if (fam_a == AF_INET6 && fam_b == AF_INET6) {
+		return v6_v6_equal (SIN6 (sa), SIN6 (sb));
+	}
+#endif
+	return FALSE;
+}
+
+gboolean
+gdm_address_is_loopback (struct sockaddr_storage *sa)
+{
+	switch(sa->ss_family){
+#ifdef	AF_INET6
+	case AF_INET6:
+		return IN6_IS_ADDR_LOOPBACK (&((struct sockaddr_in6 *)sa)->sin6_addr);
+		break;
+#endif
+	case AF_INET:
+		return (INADDR_LOOPBACK == (((struct sockaddr_in *)sa)->sin_addr.s_addr));
+		break;
+	default:
+		break;
+	}
+
+	return FALSE;
+}
+
+void
+gdm_address_get_info (struct sockaddr_storage *ss,
+		      char                   **hostp,
+		      char                   **servp)
+{
+	char host [NI_MAXHOST];
+	char serv [NI_MAXSERV];
+
+	host [0] = '\0';
+	serv [0] = '\0';
+	getnameinfo ((const struct sockaddr *)ss,
+		     sizeof (struct sockaddr_storage),
+		     host, sizeof (host),
+		     serv, sizeof (serv),
+		     NI_NUMERICHOST | NI_NUMERICSERV);
+
+	if (servp != NULL) {
+		*servp = g_strdup (serv);
+	}
+	if (hostp != NULL) {
+		*hostp = g_strdup (host);
+	}
+}
+
 /**
  * ve_clearenv:
  *
diff --git a/common/gdm-common.h b/common/gdm-common.h
index 09c8960a..c189d41a 100644
--- a/common/gdm-common.h
+++ b/common/gdm-common.h
@@ -28,13 +28,24 @@
 #include <errno.h>
 #include <sys/types.h>
 #include <sys/wait.h>
+#include <sys/socket.h>
 #include <locale.h>
+#include <netdb.h>
 
 #include "ve-signal.h"
 #include "gdm-common-config.h"
 #include "gdm-config.h"
 
 G_BEGIN_DECLS
+
+
+gboolean     gdm_address_equal        (struct sockaddr_storage *sa,
+                                       struct sockaddr_storage *sb);
+gboolean     gdm_address_is_loopback  (struct sockaddr_storage *sa);
+void         gdm_address_get_info     (struct sockaddr_storage *sa,
+                                       char                   **host,
+                                       char                   **port);
+
 void           ve_clearenv (void);
 char *	       ve_first_word (const char *s);
 gboolean       ve_first_word_executable (const char *s,
diff --git a/common/gdm-config.c b/common/gdm-config.c
index 38748655..52cfaf04 100644
--- a/common/gdm-config.c
+++ b/common/gdm-config.c
@@ -1107,14 +1107,14 @@ gdm_config_process_all (GdmConfig *config,
 }
 
 gboolean
-gdm_config_get_value (GdmConfig       *config,
-		      const char      *group,
-		      const char      *key,
-		      GdmConfigValue **valuep)
+gdm_config_peek_value (GdmConfig             *config,
+		       const char            *group,
+		       const char            *key,
+		       const GdmConfigValue **valuep)
 {
-	gboolean        ret;
-	char           *key_path;
-	GdmConfigValue *value;
+	gboolean              ret;
+	char                 *key_path;
+	const GdmConfigValue *value;
 
 	g_return_val_if_fail (config != NULL, FALSE);
 
@@ -1128,7 +1128,7 @@ gdm_config_get_value (GdmConfig       *config,
 
 	if (valuep != NULL) {
 		if (ret) {
-			*valuep = gdm_config_value_copy (value);
+			*valuep = value;
 		} else {
 			*valuep = NULL;
 		}
@@ -1138,6 +1138,23 @@ gdm_config_get_value (GdmConfig       *config,
 }
 
 gboolean
+gdm_config_get_value (GdmConfig       *config,
+		      const char      *group,
+		      const char      *key,
+		      GdmConfigValue **valuep)
+{
+	gboolean              res;
+	const GdmConfigValue *value;
+
+	res = gdm_config_peek_value (config, group, key, &value);
+	if (valuep != NULL) {
+		*valuep = (value == NULL) ? NULL : gdm_config_value_copy (value);
+	}
+
+	return res;
+}
+
+gboolean
 gdm_config_set_value (GdmConfig       *config,
 		      const char      *group,
 		      const char      *key,
@@ -1153,6 +1170,23 @@ gdm_config_set_value (GdmConfig       *config,
 	return TRUE;
 }
 
+static gboolean
+gdm_config_peek_value_for_id (GdmConfig             *config,
+			      int                    id,
+			      const GdmConfigValue **valuep)
+{
+	const GdmConfigEntry *entry;
+
+	g_return_val_if_fail (config != NULL, FALSE);
+
+	entry = gdm_config_lookup_entry_for_id (config, id);
+	if (entry == NULL) {
+		return FALSE;
+	}
+
+	return gdm_config_peek_value (config, entry->group, entry->key, valuep);
+}
+
 gboolean
 gdm_config_get_value_for_id (GdmConfig       *config,
 			     int              id,
@@ -1188,27 +1222,41 @@ gdm_config_set_value_for_id (GdmConfig      *config,
 }
 
 gboolean
-gdm_config_get_string_for_id (GdmConfig       *config,
-			      int              id,
-			      char           **strp)
+gdm_config_peek_string_for_id (GdmConfig       *config,
+			       int              id,
+			       const char     **strp)
 {
-	GdmConfigValue *value;
-	const char     *str;
-	gboolean        res;
+	const GdmConfigValue *value;
+	const char           *str;
+	gboolean              res;
 
 	g_return_val_if_fail (config != NULL, FALSE);
 
-	res = gdm_config_get_value_for_id (config, id, &value);
+	res = gdm_config_peek_value_for_id (config, id, &value);
 	if (! res) {
 		return FALSE;
 	}
 
 	str = gdm_config_value_get_string (value);
 	if (strp != NULL) {
-		*strp = g_strdup (str);
+		*strp = str;
 	}
 
-	gdm_config_value_free (value);
+	return res;
+}
+
+gboolean
+gdm_config_get_string_for_id (GdmConfig       *config,
+			      int              id,
+			      char           **strp)
+{
+	gboolean    res;
+	const char *str;
+
+	res = gdm_config_peek_string_for_id (config, id, &str);
+	if (strp != NULL) {
+		*strp = g_strdup (str);
+	}
 
 	return res;
 }
@@ -1240,6 +1288,32 @@ gdm_config_get_bool_for_id (GdmConfig       *config,
 }
 
 gboolean
+gdm_config_get_int_for_id (GdmConfig       *config,
+			   int              id,
+			   int             *integerp)
+{
+	GdmConfigValue *value;
+	gboolean        integer;
+	gboolean        res;
+
+	g_return_val_if_fail (config != NULL, FALSE);
+
+	res = gdm_config_get_value_for_id (config, id, &value);
+	if (! res) {
+		return FALSE;
+	}
+
+	integer = gdm_config_value_get_int (value);
+	if (integerp != NULL) {
+		*integerp = integer;
+	}
+
+	gdm_config_value_free (value);
+
+	return res;
+}
+
+gboolean
 gdm_config_set_string_for_id (GdmConfig      *config,
 			      int             id,
 			      char           *str)
@@ -1276,3 +1350,22 @@ gdm_config_set_bool_for_id (GdmConfig      *config,
 
 	return res;
 }
+
+gboolean
+gdm_config_set_int_for_id (GdmConfig      *config,
+			   int             id,
+			   int             integer)
+{
+	GdmConfigValue *value;
+	gboolean        res;
+
+	g_return_val_if_fail (config != NULL, FALSE);
+
+	value = gdm_config_value_new (GDM_CONFIG_VALUE_INT);
+	gdm_config_value_set_int (value, integer);
+
+	res = gdm_config_set_value_for_id (config, id, value);
+	gdm_config_value_free (value);
+
+	return res;
+}
diff --git a/common/gdm-config.h b/common/gdm-config.h
index 554a96cb..eb3831ea 100644
--- a/common/gdm-config.h
+++ b/common/gdm-config.h
@@ -125,7 +125,10 @@ char **                gdm_config_get_keys_for_group     (GdmConfig       *confi
 							  gsize           *length,
 							  GError         **error);
 
-
+gboolean               gdm_config_peek_value             (GdmConfig             *config,
+							  const char            *group,
+							  const char            *key,
+							  const GdmConfigValue **value);
 gboolean               gdm_config_get_value              (GdmConfig       *config,
 							  const char      *group,
 							  const char      *key,
@@ -135,6 +138,7 @@ gboolean               gdm_config_set_value              (GdmConfig       *confi
 							  const char      *key,
 							  GdmConfigValue  *value);
 
+/* convenience functions */
 gboolean               gdm_config_get_value_for_id       (GdmConfig       *config,
 							  int              id,
 							  GdmConfigValue **value);
@@ -142,18 +146,27 @@ gboolean               gdm_config_set_value_for_id       (GdmConfig       *confi
 							  int              id,
 							  GdmConfigValue  *value);
 
+gboolean               gdm_config_peek_string_for_id     (GdmConfig       *config,
+							  int              id,
+							  const char     **str);
 gboolean               gdm_config_get_string_for_id      (GdmConfig       *config,
 							  int              id,
 							  char           **str);
 gboolean               gdm_config_get_bool_for_id        (GdmConfig       *config,
 							  int              id,
 							  gboolean        *bool);
+gboolean               gdm_config_get_int_for_id         (GdmConfig       *config,
+							  int              id,
+							  int             *integer);
 gboolean               gdm_config_set_string_for_id      (GdmConfig       *config,
 							  int              id,
 							  char            *str);
 gboolean               gdm_config_set_bool_for_id        (GdmConfig       *config,
 							  int              id,
 							  gboolean         bool);
+gboolean               gdm_config_set_int_for_id         (GdmConfig       *config,
+							  int              id,
+							  int              integer);
 
 /* Config Values */
 
diff --git a/common/gdm-log.c b/common/gdm-log.c
new file mode 100644
index 00000000..9182359e
--- /dev/null
+++ b/common/gdm-log.c
@@ -0,0 +1,185 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ *
+ * Copyright (C) 2007 William Jon McCann <mccann@jhu.edu>
+ *
+ * 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.
+ *
+ * Authors: William Jon McCann <mccann@jhu.edu>
+ *
+ */
+
+#include "config.h"
+
+#include <stdio.h>
+#include <string.h>
+#include <stdarg.h>
+#include <signal.h>
+#include <time.h>
+#include <unistd.h>
+
+#include <syslog.h>
+
+#include <glib.h>
+#include <glib/gstdio.h>
+
+#include "gdm-log.h"
+
+static gboolean initialized = FALSE;
+static int      syslog_levels = (G_LOG_LEVEL_ERROR | G_LOG_LEVEL_CRITICAL | G_LOG_LEVEL_WARNING);
+
+static void
+log_level_to_priority_and_prefix (GLogLevelFlags log_level,
+				  int           *priorityp,
+				  const char   **prefixp)
+{
+	int         priority;
+	const char *prefix;
+
+	/* Process the message prefix and priority */
+	switch (log_level & G_LOG_LEVEL_MASK) {
+	case G_LOG_FLAG_FATAL:
+		priority = LOG_EMERG;
+		prefix = "FATAL";
+		break;
+	case G_LOG_LEVEL_ERROR:
+		priority = LOG_ERR;
+		prefix = "ERROR";
+		break;
+	case G_LOG_LEVEL_CRITICAL:
+		priority = LOG_CRIT;
+		prefix = "CRITICAL";
+		break;
+	case G_LOG_LEVEL_WARNING:
+		priority = LOG_WARNING;
+		prefix = "WARNING";
+		break;
+	case G_LOG_LEVEL_MESSAGE:
+		priority = LOG_NOTICE;
+		prefix = "MESSAGE";
+		break;
+	case G_LOG_LEVEL_INFO:
+		priority = LOG_INFO;
+		prefix = "INFO";
+		break;
+	case G_LOG_LEVEL_DEBUG:
+		/* if debug was requested then bump this up to ERROR
+		 * to ensure it is seen in a log */
+		if (syslog_levels & G_LOG_LEVEL_DEBUG) {
+			priority = LOG_WARNING;
+		} else {
+			priority = LOG_DEBUG;
+		}
+		prefix = "DEBUG";
+		break;
+	default:
+		priority = LOG_DEBUG;
+		prefix = "UNKNOWN";
+		break;
+	}
+
+	if (priorityp != NULL) {
+		*priorityp = priority;
+	}
+	if (prefixp != NULL) {
+		*prefixp = prefix;
+	}
+}
+
+void
+gdm_log_default_handler (const gchar   *log_domain,
+			 GLogLevelFlags log_level,
+			 const gchar   *message,
+			 gpointer	unused_data)
+{
+	GString     *gstring;
+	int          priority;
+	const char  *level_prefix;
+	char        *string;
+	gboolean     do_log;
+	gboolean     is_fatal;
+
+	is_fatal = (log_level & G_LOG_FLAG_FATAL) != 0;
+
+	do_log = (log_level & syslog_levels);
+	if (! do_log) {
+		return;
+	}
+
+	if (! initialized) {
+		gdm_log_init ();
+	}
+
+	log_level_to_priority_and_prefix (log_level,
+					  &priority,
+					  &level_prefix);
+
+	gstring = g_string_new (NULL);
+
+	if (log_domain != NULL) {
+		g_string_append (gstring, log_domain);
+		g_string_append_c (gstring, '-');
+	}
+	g_string_append (gstring, level_prefix);
+
+	g_string_append (gstring, ": ");
+	if (message == NULL) {
+		g_string_append (gstring, "(NULL) message");
+	} else {
+		g_string_append (gstring, message);
+	}
+	if (is_fatal) {
+		g_string_append (gstring, "\naborting...\n");
+	} else {
+		g_string_append (gstring, "\n");
+	}
+
+	string = g_string_free (gstring, FALSE);
+
+	syslog (priority, "%s", string);
+
+	g_free (string);
+}
+
+void
+gdm_log_set_debug (gboolean debug)
+{
+	if (debug) {
+		syslog_levels |= G_LOG_LEVEL_DEBUG;
+	} else {
+		syslog_levels &= ~G_LOG_LEVEL_DEBUG;
+    	}
+}
+
+void
+gdm_log_init (void)
+{
+	const char *prg_name;
+
+	g_log_set_default_handler (gdm_log_default_handler, NULL);
+
+	prg_name = g_get_prgname ();
+
+	openlog (prg_name, LOG_PERROR|LOG_PID, LOG_DAEMON);
+
+	initialized = TRUE;
+}
+
+void
+gdm_log_shutdown (void)
+{
+	closelog ();
+	initialized = FALSE;
+}
+
diff --git a/common/gdm-log.h b/common/gdm-log.h
new file mode 100644
index 00000000..3d6effbc
--- /dev/null
+++ b/common/gdm-log.h
@@ -0,0 +1,50 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
+ *
+ * Copyright (C) 2007 William Jon McCann <mccann@jhu.edu>
+ *
+ * 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.
+ *
+ * Authors: William Jon McCann <mccann@jhu.edu>
+ *
+ */
+
+#ifndef __GDM_LOG_H
+#define __GDM_LOG_H
+
+#include <stdarg.h>
+#include <glib.h>
+
+G_BEGIN_DECLS
+
+void      gdm_log_default_handler (const gchar   *log_domain,
+                                   GLogLevelFlags log_level,
+                                   const gchar   *message,
+                                   gpointer	 unused_data);
+void      gdm_log_set_debug       (gboolean       debug);
+void      gdm_log_init            (void);
+void      gdm_log_shutdown        (void);
+
+/* compatibility */
+#define   gdm_fail               g_critical
+#define   gdm_error              g_warning
+#define   gdm_info               g_message
+#define   gdm_debug              g_debug
+
+#define   gdm_assert             g_assert
+#define   gdm_assert_not_reached g_assert_not_reached
+
+G_END_DECLS
+
+#endif /* __GDM_LOG_H */