merged plugin-test branch into trunk.

git-svn-id: svn://sylpheed.sraoss.jp/sylpheed/trunk@2164 ee746299-78ed-0310-b773-934348b2243d

16 files changed, 1642 insertions, 108 deletions

diff --git a/src/Makefile.am b/src/Makefile.am
index bc25307e..bfe67d2d 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -89,6 +89,8 @@ sylpheed_SOURCES = \
 	trayicon.c trayicon.h \
 	printing.c printing.h \
 	sslmanager.c sslmanager.h \
+	plugin_manager.c plugin_manager.h \
+	update_check.c update_check.h \
 	quote_fmt_lex.l quote_fmt_lex.h \
 	quote_fmt_parse.y quote_fmt.h \
 	sylpheed-marshal.c sylpheed-marshal.h
@@ -100,11 +102,33 @@ BUILT_SOURCES = \
 	sylpheed-marshal.c \
 	sylpheed-marshal.h
 
+lib_LTLIBRARIES = libsylpheed-plugin-0.la
+
+libsylpheed_plugin_0_la_SOURCES = \
+	plugin.c
+
+libsylpheed_plugin_0includedir=$(includedir)/sylpheed
+libsylpheed_plugin_0include_HEADERS = \
+	plugin.h
+
+if NATIVE_WIN32
+no_undefined = -no-undefined
+export_symbols = -export-symbols libsylpheed-plugin-0.def
+endif
+
+libsylpheed_plugin_0_la_LDFLAGS = \
+	-export-dynamic $(no_undefined) $(export_symbols)
+
+libsylpheed_plugin_0_la_LIBADD = \
+	$(GTK_LIBS) \
+	../libsylph/libsylph-0.la
+
 EXTRA_DIST = \
 	quote_fmt_parse.h \
 	sylpheed-marshal.list \
 	version.h.in \
-	sylpheed.rc.in
+	sylpheed.rc.in \
+	libsylpheed-plugin-0.def
 
 INCLUDES = \
 	-DG_LOG_DOMAIN=\"Sylpheed\" \
@@ -128,13 +152,15 @@ sylpheed_LDADD = \
 	$(GPGME_LIBS) \
 	$(LDAP_LIBS) \
 	$(LIBICONV) \
-	../libsylph/libsylph.la \
+	libsylpheed-plugin-0.la \
+	../libsylph/libsylph-0.la \
 	$(SYLPHEED_RES)
 
 AM_CPPFLAGS = \
 	-DLOCALEDIR=\""$(localedir)"\" \
 	-DMANUALDIR=\""$(manualdir)"\" \
 	-DFAQDIR=\""$(faqdir)"\" \
+	-DPLUGINDIR=\""$(plugindir)"\" \
 	-DTARGET_ALIAS=\""$(target_triplet)"\" \
 	-DSYSCONFDIR=\""$(sysconfdir)"\"
 
diff --git a/src/about.c b/src/about.c
index 6e22e9b2..01e7a24d 100644
--- a/src/about.c
+++ b/src/about.c
@@ -1,6 +1,6 @@
 /*
  * Sylpheed -- a GTK+ based, lightweight, and fast e-mail client
- * Copyright (C) 1999-2008 Hiroyuki Yamamoto
+ * Copyright (C) 1999-2009 Hiroyuki Yamamoto
  *
  * 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
@@ -175,7 +175,7 @@ static void about_create(void)
 	gtk_box_pack_start(GTK_BOX(vbox), label, FALSE, FALSE, 0);
 
 	label = gtk_label_new
-		("Copyright (C) 1999-2008 Hiroyuki Yamamoto <hiro-y@kcn.ne.jp>");
+		("Copyright (C) 1999-2009 Hiroyuki Yamamoto <hiro-y@kcn.ne.jp>");
 	gtk_label_set_selectable(GTK_LABEL(label), TRUE);
 	gtk_box_pack_start(GTK_BOX(vbox), label, FALSE, FALSE, 0);
 
diff --git a/src/folderview.c b/src/folderview.c
index 17272447..1c0aeb7a 100644
--- a/src/folderview.c
+++ b/src/folderview.c
@@ -69,6 +69,7 @@
 #include "inc.h"
 #include "send_message.h"
 #include "virtual.h"
+#include "plugin.h"
 
 enum
 {
@@ -1773,10 +1774,11 @@ static gboolean folderview_menu_popup(FolderView *folderview,
 	SET_VISIBILITY(ifactory, "/Edit search condition...",
 		       item->stype == F_VIRTUAL);
 
-
 #undef SET_SENS
 #undef SET_VISIBILITY
 
+	syl_plugin_signal_emit("folderview-menu-popup", ifactory);
+
 	gtk_menu_popup(GTK_MENU(popup), NULL, NULL, NULL, NULL,
 		       event->button, event->time);
 
@@ -2282,6 +2284,16 @@ static void folderview_new_folder_cb(FolderView *folderview, guint action,
 	if (!new_folder) return;
 	AUTORELEASE_STR(new_folder, {g_free(new_folder); return;});
 
+#ifdef G_OS_WIN32
+	p = strpbrk(new_folder, "\\/:*?\"<>|");
+	if ((p && FOLDER_TYPE(item->folder) != F_IMAP) || (p && *p != '/') ||
+	    (p && p == '/' &&
+	     FOLDER_TYPE(item->folder) == F_IMAP && *(p + 1) != '\0')) {
+		alertpanel_error(_("`%c' can't be included in folder name."),
+				 *p);
+		return;
+	}
+#else
 	p = strchr(new_folder, G_DIR_SEPARATOR);
 	if ((p && FOLDER_TYPE(item->folder) != F_IMAP) ||
 	    (p && FOLDER_TYPE(item->folder) == F_IMAP && *(p + 1) != '\0')) {
@@ -2289,6 +2301,7 @@ static void folderview_new_folder_cb(FolderView *folderview, guint action,
 				 G_DIR_SEPARATOR);
 		return;
 	}
+#endif
 
 	name = trim_string(new_folder, 32);
 	AUTORELEASE_STR(name, {g_free(name); return;});
diff --git a/src/libsylpheed-plugin-0.def b/src/libsylpheed-plugin-0.def
new file mode 100644
index 00000000..af7f91cd
--- /dev/null
+++ b/src/libsylpheed-plugin-0.def
@@ -0,0 +1,41 @@
+; c:\MinGW\bin\dlltool.exe -z libsylpheed-plugin-0.def --export-all-symbols .libs/plugin.o

+EXPORTS

+	syl_plugin_add_factory_item @ 1

+	syl_plugin_add_menuitem @ 2

+	syl_plugin_add_symbol @ 3

+	syl_plugin_app_will_exit @ 4

+	syl_plugin_folder_sel @ 5

+	syl_plugin_folder_sel_full @ 6

+	syl_plugin_folderview_get @ 7

+	syl_plugin_folderview_get_selected_item @ 8

+	syl_plugin_get_prog_version @ 9

+	syl_plugin_get_type @ 10

+	syl_plugin_inc_lock @ 11

+	syl_plugin_inc_mail @ 12

+	syl_plugin_inc_unlock @ 13

+	syl_plugin_init_lib @ 14

+	syl_plugin_input_dialog @ 15

+	syl_plugin_input_dialog_with_invisible @ 16

+	syl_plugin_load @ 17

+	syl_plugin_load_all @ 18

+	syl_plugin_main_window_get @ 19

+	syl_plugin_main_window_popup @ 20

+	syl_plugin_manage_window_set_transient @ 21

+	syl_plugin_manage_window_signals_connect @ 22

+	syl_plugin_messageview_create_with_new_window @ 23

+	syl_plugin_open_message @ 24

+	syl_plugin_open_message_by_new_window @ 25

+	syl_plugin_signal_connect @ 26

+	syl_plugin_signal_disconnect @ 27

+	syl_plugin_signal_emit @ 28

+	syl_plugin_sumary_select_by_msgnum @ 29

+	syl_plugin_summary_select_by_msginfo @ 30

+	syl_plugin_summary_view_get @ 31

+	syl_plugin_unload_all @ 32

+	syl_plugin_get_module_list @ 33

+	syl_plugin_get_info @ 34

+	syl_plugin_check_version @ 35

+	syl_plugin_menu_set_sensitive @ 36

+	syl_plugin_menu_set_sensitive_all @ 37

+	syl_plugin_menu_set_active @ 38

+	syl_plugin_manage_window_get_focus_window @ 39

diff --git a/src/main.c b/src/main.c
index 8c934f44..50e7cc0a 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1,6 +1,6 @@
 /*
  * Sylpheed -- a GTK+ based, lightweight, and fast e-mail client
- * Copyright (C) 1999-2008 Hiroyuki Yamamoto
+ * Copyright (C) 1999-2009 Hiroyuki Yamamoto
  *
  * 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
@@ -75,11 +75,16 @@
 #include "logwindow.h"
 #include "folder.h"
 #include "setup.h"
+#include "sylmain.h"
 #include "utils.h"
 #include "gtkutils.h"
 #include "socket.h"
 #include "stock_pixmap.h"
 #include "trayicon.h"
+#include "plugin.h"
+#include "plugin_manager.h"
+#include "foldersel.h"
+#include "update_check.h"
 
 #if USE_GPGME
 #  include "rfc2015.h"
@@ -136,6 +141,7 @@ static void setup_rc_dir		(void);
 static void check_gpg			(void);
 static void set_log_handlers		(gboolean	 enable);
 static void register_system_events	(void);
+static void plugin_init			(void);
 
 static gchar *get_socket_name		(void);
 static gint prohibit_duplicate_launch	(void);
@@ -174,6 +180,10 @@ static void send_queue			(void);
 		exit(val);		\
 }
 
+static void load_cb(GObject *obj, GModule *module, gpointer data)
+{
+	g_print("load_cb: %p (%s), %p\n", module, module ? g_module_name(module) : "(null)", data);
+}
 
 int main(int argc, char *argv[])
 {
@@ -183,15 +193,11 @@ int main(int argc, char *argv[])
 #ifdef G_OS_WIN32
 	GList *iconlist = NULL;
 #endif
+	GObject *syl_app;
 
 	app_init();
 	parse_cmd_opt(argc, argv);
 
-	sock_init();
-#if USE_SSL
-	ssl_init();
-#endif
-
 	/* check and create (unix domain) socket for remote operation */
 	lock_socket = prohibit_duplicate_launch();
 	if (lock_socket < 0) return 0;
@@ -205,6 +211,8 @@ int main(int argc, char *argv[])
 	gtk_set_locale();
 	gtk_init(&argc, &argv);
 
+	syl_app = syl_app_create();
+
 	gdk_rgb_init();
 	gtk_widget_set_default_colormap(gdk_rgb_get_cmap());
 	gtk_widget_set_default_visual(gdk_rgb_get_visual());
@@ -324,7 +332,13 @@ int main(int argc, char *argv[])
 
 	inc_autocheck_timer_init(mainwin);
 
+	plugin_init();
+
+	g_signal_emit_by_name(syl_app, "init-done");
+
 	remote_command_exec();
+	if (prefs_common.auto_update_check)
+		update_check(FALSE);
 
 	gtk_main();
 
@@ -568,70 +582,9 @@ static gint get_queued_message_num(void)
 
 static void app_init(void)
 {
-#ifdef G_OS_WIN32
-	gchar *newpath;
-	const gchar *lang_env;
-
-	/* disable locale variable such as "LANG=1041" */
-
-#define DISABLE_DIGIT_LOCALE(envstr)			\
-{							\
-	lang_env = g_getenv(envstr);			\
-	if (lang_env && g_ascii_isdigit(lang_env[0]))	\
-		g_unsetenv(envstr);			\
-}
-
-	DISABLE_DIGIT_LOCALE("LC_ALL");
-	DISABLE_DIGIT_LOCALE("LANG");
-	DISABLE_DIGIT_LOCALE("LC_CTYPE");
-	DISABLE_DIGIT_LOCALE("LC_MESSAGES");
-
-#undef DISABLE_DIGIT_LOCALE
-
-	g_unsetenv("LANGUAGE");
-#endif
-
-#ifdef HAVE_LOCALE_H
-	setlocale(LC_ALL, "");
-#endif
+	syl_init();
 
 	prog_version = PROG_VERSION;
-	set_startup_dir();
-
-#ifdef G_OS_WIN32
-	/* include startup directory into %PATH% for GSpawn */
-	newpath = g_strconcat(get_startup_dir(), ";", g_getenv("PATH"), NULL);
-	g_setenv("PATH", newpath, TRUE);
-	g_free(newpath);
-#endif
-
-#ifdef ENABLE_NLS
-	if (g_path_is_absolute(LOCALEDIR))
-		bindtextdomain(PACKAGE, LOCALEDIR);
-	else {
-		gchar *locale_dir;
-
-		locale_dir = g_strconcat(get_startup_dir(), G_DIR_SEPARATOR_S,
-					 LOCALEDIR, NULL);
-#ifdef G_OS_WIN32
-		{
-			gchar *locale_dir_;
-
-			locale_dir_ = g_locale_from_utf8(locale_dir, -1,
-							 NULL, NULL, NULL);
-			if (locale_dir_) {
-				g_free(locale_dir);
-				locale_dir = locale_dir_;
-			}
-		}
-#endif /* G_OS_WIN32 */
-		bindtextdomain(PACKAGE, locale_dir);
-		g_free(locale_dir);
-	}
-
-	bind_textdomain_codeset(PACKAGE, CS_UTF_8);
-	textdomain(PACKAGE);
-#endif /* ENABLE_NLS */
 
 #ifdef G_OS_WIN32
 	read_ini_file();
@@ -704,24 +657,7 @@ static void setup_rc_dir(void)
 	}
 #endif /* !G_OS_WIN32 */
 
-	if (!is_dir_exist(get_rc_dir())) {
-		if (make_dir_hier(get_rc_dir()) < 0)
-			exit(1);
-	}
-
-	MAKE_DIR_IF_NOT_EXIST(get_mail_base_dir());
-
-	CHDIR_EXIT_IF_FAIL(get_rc_dir(), 1);
-
-	MAKE_DIR_IF_NOT_EXIST(get_imap_cache_dir());
-	MAKE_DIR_IF_NOT_EXIST(get_news_cache_dir());
-	MAKE_DIR_IF_NOT_EXIST(get_mime_tmp_dir());
-	MAKE_DIR_IF_NOT_EXIST(get_tmp_dir());
-	MAKE_DIR_IF_NOT_EXIST(UIDL_DIR);
-
-	/* remove temporary files */
-	remove_all_files(get_tmp_dir());
-	remove_all_files(get_mime_tmp_dir());
+	syl_setup_rc_dir();
 }
 
 void app_will_exit(gboolean force)
@@ -760,6 +696,8 @@ void app_will_exit(gboolean force)
 		manage_window_focus_in(mainwin->window, NULL, NULL);
 	}
 
+	g_signal_emit_by_name(syl_app_get(), "app-exit");
+
 	inc_autocheck_timer_remove();
 
 	if (prefs_common.clean_on_exit)
@@ -773,36 +711,26 @@ void app_will_exit(gboolean force)
 			procmsg_remove_all_cached_messages(FOLDER(ac->folder));
 	}
 
+	syl_plugin_unload_all();
+
 	trayicon_destroy(mainwin->tray_icon);
 
 	/* save all state before exiting */
-	folder_write_list();
 	summary_write_cache(mainwin->summaryview);
-
 	main_window_get_size(mainwin);
 	main_window_get_position(mainwin);
-	prefs_common_write_config();
-	filter_write_config();
-	account_write_config_all();
+	syl_save_all_state();
 	addressbook_export_to_file();
 
 	filename = g_strconcat(get_rc_dir(), G_DIR_SEPARATOR_S, MENU_RC, NULL);
 	gtk_accel_map_save(filename);
 	g_free(filename);
 
-	/* remove temporary files */
-	remove_all_files(get_tmp_dir());
-	remove_all_files(get_mime_tmp_dir());
-
-	set_log_handlers(FALSE);
-	close_log_file();
+	/* remove temporary files, close log file, socket cleanup */
+	syl_cleanup();
 	lock_socket_remove();
 
-#if USE_SSL
-	ssl_done();
-#endif
 	cleanup_console();
-	sock_cleanup();
 
 	if (gtk_main_level() > 0)
 		gtk_main_quit();
@@ -1080,6 +1008,72 @@ static void register_system_events(void)
 }
 #endif
 
+static void plugin_init(void)
+{
+	MainWindow *mainwin;
+
+	mainwin = main_window_get();
+
+	if (syl_plugin_init_lib() != 0)
+		return;
+
+	syl_plugin_add_symbol("prog_version", prog_version);
+	syl_plugin_add_symbol("main_window_get", main_window_get);
+	syl_plugin_add_symbol("main_window_popup", main_window_popup);
+	syl_plugin_add_symbol("app_will_exit", app_will_exit);
+	syl_plugin_add_symbol("main_window_menu_factory",
+			      mainwin->menu_factory);
+
+	syl_plugin_add_symbol("folderview", mainwin->folderview);
+	syl_plugin_add_symbol("folderview_get_selected_item",
+			      folderview_get_selected_item);
+	syl_plugin_add_symbol("folderview_mail_popup_factory",
+			      mainwin->folderview->mail_factory);
+
+	syl_plugin_add_symbol("summaryview", mainwin->summaryview);
+	syl_plugin_add_symbol("summary_select_by_msgnum",
+			      summary_select_by_msgnum);
+	syl_plugin_add_symbol("summary_select_by_msginfo",
+			      summary_select_by_msginfo);
+
+	syl_plugin_add_symbol("messageview_create_with_new_window",
+			      messageview_create_with_new_window);
+	syl_plugin_add_symbol("messageview_show", messageview_show);
+
+	syl_plugin_add_symbol("foldersel_folder_sel",
+			      foldersel_folder_sel);
+	syl_plugin_add_symbol("foldersel_folder_sel_full",
+			      foldersel_folder_sel_full);
+	syl_plugin_add_symbol("input_dialog", input_dialog);
+	syl_plugin_add_symbol("input_dialog_with_invisible",
+			      input_dialog_with_invisible);
+
+	syl_plugin_add_symbol("manage_window_set_transient",
+			      manage_window_set_transient);
+	syl_plugin_add_symbol("manage_window_signals_connect",
+			      manage_window_signals_connect);
+	syl_plugin_add_symbol("manage_window_get_focus_window",
+			      manage_window_get_focus_window);
+
+	syl_plugin_add_symbol("inc_mail", inc_mail);
+	syl_plugin_add_symbol("inc_lock", inc_lock);
+	syl_plugin_add_symbol("inc_unlock", inc_unlock);
+
+	syl_plugin_signal_connect("plugin-load", G_CALLBACK(load_cb), NULL);
+
+#ifdef G_OS_WIN32
+	{
+		gchar *path;
+		path = g_strconcat(get_startup_dir(), G_DIR_SEPARATOR_S,
+				   "plugins", NULL);
+		syl_plugin_load_all(path);
+		g_free(path);
+	}
+#else
+	syl_plugin_load_all(PLUGINDIR);
+#endif
+}
+
 static gchar *get_socket_name(void)
 {
 	static gchar *filename = NULL;
diff --git a/src/mainwindow.c b/src/mainwindow.c
index e0a43dd8..7d9736c7 100644
--- a/src/mainwindow.c
+++ b/src/mainwindow.c
@@ -79,6 +79,7 @@
 #include "prefs_template.h"
 #include "prefs_search_folder.h"
 #include "prefs_toolbar.h"
+#include "plugin_manager.h"
 #include "action.h"
 #include "account.h"
 #include "account_dialog.h"
@@ -95,6 +96,7 @@
 #include "codeconv.h"
 #include "about.h"
 #include "manual.h"
+#include "update_check.h"
 #include "version.h"
 
 #define AC_LABEL_WIDTH	240
@@ -495,6 +497,9 @@ static void prefs_filter_open_cb	(MainWindow	*mainwin,
 static void prefs_template_open_cb	(MainWindow	*mainwin,
 					 guint		 action,
 					 GtkWidget	*widget);
+static void plugin_manager_open_cb	(MainWindow	*mainwin,
+					 guint		 action,
+					 GtkWidget	*widget);
 #ifndef G_OS_WIN32
 static void prefs_actions_open_cb	(MainWindow	*mainwin,
 					 guint		 action,
@@ -522,6 +527,9 @@ static void faq_open_cb		 (MainWindow	*mainwin,
 static void help_cmdline_cb	 (MainWindow	*mainwin,
 				  guint		 action,
 				  GtkWidget	*widget);
+static void update_check_cb	 (MainWindow	*mainwin,
+				  guint		 action,
+				  GtkWidget	*widget);
 
 static void scan_tree_func	 (Folder	*folder,
 				  FolderItem	*item,
@@ -857,6 +865,8 @@ static GtkItemFactoryEntry mainwin_entries[] =
 #ifndef G_OS_WIN32
 	{N_("/_Configuration/_Actions..."),	NULL, prefs_actions_open_cb, 0, NULL},
 #endif
+	{N_("/_Configuration/Plug-in _manager..."),
+						NULL, plugin_manager_open_cb, 0, NULL},
 	{N_("/_Configuration/---"),		NULL, NULL, 0, "<Separator>"},
 	{N_("/_Configuration/_Preferences for current account..."),
 						NULL, prefs_account_open_cb, 0, NULL},
@@ -879,6 +889,8 @@ static GtkItemFactoryEntry mainwin_entries[] =
 	{N_("/_Help/_FAQ/_Italian"),		NULL, faq_open_cb, MANUAL_LANG_IT, NULL},
 	{N_("/_Help/_Command line options"),	NULL, help_cmdline_cb, 0, NULL},
 	{N_("/_Help/---"),			NULL, NULL, 0, "<Separator>"},
+	{N_("/_Help/_Update check..."),		NULL, update_check_cb, 0, NULL},
+	{N_("/_Help/---"),			NULL, NULL, 0, "<Separator>"},
 	{N_("/_Help/_About"),			NULL, about_show, 0, NULL}
 };
 
@@ -3852,6 +3864,12 @@ static void prefs_template_open_cb(MainWindow *mainwin, guint action,
 	prefs_template_open();
 }
 
+static void plugin_manager_open_cb(MainWindow *mainwin, guint action,
+				   GtkWidget *widget)
+{
+	plugin_manager_open();
+}
+
 #ifndef G_OS_WIN32
 static void prefs_actions_open_cb(MainWindow *mainwin, guint action,
 				  GtkWidget *widget)
@@ -4027,6 +4045,12 @@ static void help_cmdline_cb(MainWindow *mainwin, guint action,
 	help_command_line_show();
 }
 
+static void update_check_cb(MainWindow *mainwin, guint action,
+			    GtkWidget *widget)
+{
+	update_check(TRUE);
+}
+
 static void scan_tree_func(Folder *folder, FolderItem *item, gpointer data)
 {
 	MainWindow *mainwin = (MainWindow *)data;
diff --git a/src/manage_window.c b/src/manage_window.c
index fe9f2b86..b21a3b22 100644
--- a/src/manage_window.c
+++ b/src/manage_window.c
@@ -92,6 +92,11 @@ void manage_window_set_transient(GtkWindow *window)
 	}
 }
 
+void manage_window_signals_connect(GtkWindow *window)
+{
+	MANAGE_WINDOW_SIGNALS_CONNECT(window);
+}
+
 GtkWidget *manage_window_get_focus_window(void)
 {
 	return focus_window;
diff --git a/src/manage_window.h b/src/manage_window.h
index 64d48617..61369d1e 100644
--- a/src/manage_window.h
+++ b/src/manage_window.h
@@ -52,6 +52,7 @@ void manage_window_destroy		(GtkWidget	*widget,
 					 gpointer	 data);
 
 void manage_window_set_transient	(GtkWindow	*window);
+void manage_window_signals_connect	(GtkWindow	*window);
 
 GtkWidget *manage_window_get_focus_window	(void);
 
diff --git a/src/plugin.c b/src/plugin.c
new file mode 100644
index 00000000..062200ff
--- /dev/null
+++ b/src/plugin.c
@@ -0,0 +1,644 @@
+/*
+ * Sylpheed -- a GTK+ based, lightweight, and fast e-mail client
+ * Copyright (C) 1999-2009 Hiroyuki Yamamoto
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <glib.h>
+#include <gmodule.h>
+#include <gtk/gtk.h>
+
+#include "plugin.h"
+#include "utils.h"
+#include "folder.h"
+
+G_DEFINE_TYPE(SylPlugin, syl_plugin, G_TYPE_OBJECT);
+
+enum {
+	PLUGIN_LOAD,
+	PLUGIN_UNLOAD,
+	FOLDERVIEW_MENU_POPUP,
+	LAST_SIGNAL
+};
+
+#define syl_plugin_lookup_symbol(name)	g_hash_table_lookup(sym_table, name)
+
+#define SAFE_CALL(func_ptr)		{ if (func_ptr) func_ptr(); }
+#define SAFE_CALL_RET(func_ptr)		(func_ptr ? func_ptr() : NULL)
+#define SAFE_CALL_ARG1(func_ptr, arg1)	{ if (func_ptr) func_ptr(arg1); }
+#define SAFE_CALL_ARG1_RET(func_ptr, arg1) \
+				(func_ptr ? func_ptr(arg1) : NULL)
+#define SAFE_CALL_ARG2(func_ptr, arg1, arg2) \
+				{ if (func_ptr) func_ptr(arg1, arg2); }
+#define SAFE_CALL_ARG2_RET(func_ptr, arg1, arg2) \
+				(func_ptr ? func_ptr(arg1, arg2) : NULL)
+#define SAFE_CALL_ARG2_RET_VAL(func_ptr, arg1, arg2, retval) \
+				(func_ptr ? func_ptr(arg1, arg2) : retval)
+#define SAFE_CALL_ARG3(func_ptr, arg1, arg2, arg3) \
+				{ if (func_ptr) func_ptr(arg1, arg2, arg3); }
+#define SAFE_CALL_ARG3_RET(func_ptr, arg1, arg2, arg3) \
+				(func_ptr ? func_ptr(arg1, arg2, arg3) : NULL)
+#define SAFE_CALL_ARG4(func_ptr, arg1, arg2, arg3, arg4) \
+				{ if (func_ptr) func_ptr(arg1, arg2, arg3); }
+#define SAFE_CALL_ARG4_RET(func_ptr, arg1, arg2, arg3, arg4) \
+				(func_ptr ? func_ptr(arg1, arg2, arg3, arg4) : NULL)
+
+static guint plugin_signals[LAST_SIGNAL] = { 0 };
+
+static GHashTable *sym_table = NULL;
+static GSList *module_list = NULL;
+static GObject *plugin_obj = NULL;
+
+static void syl_plugin_init(SylPlugin *self)
+{
+}
+
+static void syl_plugin_class_init(SylPluginClass *klass)
+{
+	GObjectClass *gobject_class = G_OBJECT_CLASS(klass);
+
+	plugin_signals[PLUGIN_LOAD] =
+		g_signal_new("plugin-load",
+			     G_TYPE_FROM_CLASS(gobject_class),
+			     G_SIGNAL_RUN_FIRST,
+			     G_STRUCT_OFFSET(SylPluginClass, plugin_load),
+			     NULL, NULL,
+			     g_cclosure_marshal_VOID__POINTER,
+			     G_TYPE_NONE,
+			     1,
+			     G_TYPE_POINTER);
+	plugin_signals[PLUGIN_UNLOAD] =
+		g_signal_new("plugin-unload",
+			     G_TYPE_FROM_CLASS(gobject_class),
+			     G_SIGNAL_RUN_FIRST,
+			     G_STRUCT_OFFSET(SylPluginClass, plugin_unload),
+			     NULL, NULL,
+			     g_cclosure_marshal_VOID__POINTER,
+			     G_TYPE_NONE,
+			     1,
+			     G_TYPE_POINTER);
+	plugin_signals[FOLDERVIEW_MENU_POPUP] =
+		g_signal_new("folderview-menu-popup",
+			     G_TYPE_FROM_CLASS(gobject_class),
+			     G_SIGNAL_RUN_FIRST,
+			     G_STRUCT_OFFSET(SylPluginClass,
+					     folderview_menu_popup),
+			     NULL, NULL,
+			     g_cclosure_marshal_VOID__POINTER,
+			     G_TYPE_NONE,
+			     1,
+			     G_TYPE_POINTER);
+}
+
+void syl_plugin_signal_connect(const gchar *name, GCallback callback,
+			       gpointer data)
+{
+	g_signal_connect(plugin_obj, name, callback, data);
+}
+
+void syl_plugin_signal_disconnect(gpointer func, gpointer data)
+{
+	g_signal_handlers_disconnect_by_func(plugin_obj, func, data);
+}
+
+void syl_plugin_signal_emit(const gchar *name, ...)
+{
+	guint signal_id;
+
+	if (g_signal_parse_name(name, G_TYPE_FROM_INSTANCE(plugin_obj), &signal_id, NULL, FALSE)) {
+		va_list var_args;
+		va_start(var_args, name);
+		g_signal_emit_valist(plugin_obj, signal_id, 0, var_args);
+		va_end(var_args);
+	} else
+		g_warning("%s: signal '%s' not found", G_STRLOC, name);
+}
+
+gint syl_plugin_init_lib(void)
+{
+	if (!g_module_supported()) {
+		g_warning("Plug-in is not supported.");
+		return -1;
+	}
+
+	if (!sym_table) {
+		sym_table = g_hash_table_new(g_str_hash, g_str_equal);
+	}
+
+	if (!plugin_obj) {
+		plugin_obj = g_object_new(SYL_TYPE_PLUGIN, NULL);
+	}
+
+	return 0;
+}
+
+gint syl_plugin_load(const gchar *name)
+{
+	GModule *module;
+	SylPluginLoadFunc load_func = NULL;
+	gchar *file;
+
+	g_return_val_if_fail(name != NULL, -1);
+
+	debug_print("syl_plugin_load: loading %s\n", name);
+
+	if (!g_path_is_absolute(name))
+		file = g_strconcat(PLUGINDIR, G_DIR_SEPARATOR_S, name, NULL);
+	else
+		file = g_strdup(name);
+
+	module = g_module_open(file, G_MODULE_BIND_LAZY);
+	if (!module) {
+		g_warning("Cannot open module: %s: %s", name, g_module_error());
+		g_free(file);
+		return -1;
+	}
+	if (g_slist_find(module_list, module)) {
+		g_warning("Module %s is already loaded", name);
+		g_free(file);
+		return -1;
+	}
+
+	if (g_module_symbol(module, "plugin_load", (gpointer *)&load_func)) {
+		if (!syl_plugin_check_version(module)) {
+#if 0
+			g_warning("Version check failed. Skipping: %s", name);
+			g_module_close(module);
+			g_free(file);
+			return -1;
+#endif
+		}
+
+		debug_print("calling plugin_load() in %s\n",
+			    g_module_name(module));
+		load_func();
+		module_list = g_slist_prepend(module_list, module);
+		g_signal_emit(plugin_obj, plugin_signals[PLUGIN_LOAD], 0, module);
+	} else {
+		g_warning("Cannot get symbol: %s: %s", name, g_module_error());
+		g_module_close(module);
+		g_free(file);
+		return -1;
+	}
+
+	g_free(file);
+
+	return 0;
+}
+
+gint syl_plugin_load_all(const gchar *dir)
+{
+	GDir *d;
+	const gchar *dir_name;
+	gchar *path;
+	gint count = 0;
+
+	if ((d = g_dir_open(dir, 0, NULL)) == NULL) {
+		g_warning("failed to open directory: %s", dir);
+		return -1;
+	}
+
+	while ((dir_name = g_dir_read_name(d)) != NULL) {
+		if (!g_str_has_suffix(dir_name, "." G_MODULE_SUFFIX))
+			continue;
+		path = g_strconcat(dir, G_DIR_SEPARATOR_S, dir_name, NULL);
+		if (syl_plugin_load(path) == 0)
+			count++;
+		g_free(path);
+	}
+
+	g_dir_close(d);
+
+	return count;
+}
+
+void syl_plugin_unload_all(void)
+{
+	GSList *cur;
+
+	for (cur = module_list; cur != NULL; cur = cur->next) {
+		GModule *module = (GModule *)cur->data;
+		SylPluginUnloadFunc unload_func = NULL;
+
+		if (g_module_symbol(module, "plugin_unload",
+				    (gpointer *)&unload_func)) {
+			g_signal_emit(plugin_obj, plugin_signals[PLUGIN_UNLOAD],
+				      0, module);
+			debug_print("calling plugin_unload() in %s\n",
+				    g_module_name(module));
+			unload_func();
+		} else {
+			g_warning("Cannot get symbol: %s", g_module_error());
+		}
+		if (!g_module_close(module)) {
+			g_warning("Module unload failed: %s", g_module_error());
+		}
+	}
+
+	g_slist_free(module_list);
+	module_list = NULL;
+}
+
+GSList *syl_plugin_get_module_list(void)
+{
+	return module_list;
+}
+
+SylPluginInfo *syl_plugin_get_info(GModule *module)
+{
+	SylPluginInfo * (*plugin_info_func)(void);
+
+	g_return_val_if_fail(module != NULL, NULL);
+
+	debug_print("getting plugin information of %s\n",
+		    g_module_name(module));
+
+	if (g_module_symbol(module, "plugin_info",
+			    (gpointer *)&plugin_info_func)) {
+		debug_print("calling plugin_info() in %s\n",
+			    g_module_name(module));
+		return plugin_info_func();
+	} else {
+		g_warning("Cannot get symbol: %s: %s", g_module_name(module),
+			  g_module_error());
+		return NULL;
+	}
+}
+
+gboolean syl_plugin_check_version(GModule *module)
+{
+	gint (*version_func)(void);
+	gint ver;
+
+	g_return_val_if_fail(module != NULL, FALSE);
+
+	if (g_module_symbol(module, "plugin_interface_version",
+			    (gpointer *)&version_func)) {
+		debug_print("calling plugin_interface_version() in %s\n",
+			    g_module_name(module));
+		ver = version_func();
+	} else {
+		g_warning("Cannot get symbol: %s: %s", g_module_name(module),
+			  g_module_error());
+		return FALSE;
+	}
+
+	if (ver == SYL_PLUGIN_INTERFACE_VERSION) {
+		debug_print("Version OK: plugin: %d, app: %d\n",
+			    ver, SYL_PLUGIN_INTERFACE_VERSION);
+		return TRUE;
+	} else {
+		g_warning("Plugin interface version mismatch: plugin: %d, app: %d", ver, SYL_PLUGIN_INTERFACE_VERSION);
+		return FALSE;
+	}
+}
+
+gint syl_plugin_add_symbol(const gchar *name, gpointer sym)
+{
+	g_hash_table_insert(sym_table, (gpointer)name, sym);
+	return 0;
+}
+
+const gchar *syl_plugin_get_prog_version(void)
+{
+	gpointer sym;
+
+	sym = syl_plugin_lookup_symbol("prog_version");
+	return (gchar *)sym;
+}
+
+gpointer syl_plugin_main_window_get(void)
+{
+	gpointer (*func)(void);
+
+	func = syl_plugin_lookup_symbol("main_window_get");
+	return SAFE_CALL_RET(func);
+}
+
+void syl_plugin_main_window_popup(gpointer mainwin)
+{
+	void (*func)(gpointer);
+
+	func = syl_plugin_lookup_symbol("main_window_popup");
+	SAFE_CALL_ARG1(func, mainwin);
+}
+
+void syl_plugin_app_will_exit(gboolean force)
+{
+	void (*func)(gboolean);
+
+	func = syl_plugin_lookup_symbol("app_will_exit");
+	SAFE_CALL_ARG1(func, force);
+}
+
+static GtkItemFactory *get_item_factory(const gchar *path)
+{
+	GtkItemFactory *ifactory;
+
+	if (!path)
+		return NULL;
+
+	if (strncmp(path, "<Main>", 6) == 0)
+		ifactory = syl_plugin_lookup_symbol("main_window_menu_factory");
+	else if (strncmp(path, "<MailFolder>", 12) == 0)
+		ifactory = syl_plugin_lookup_symbol("folderview_mail_popup_factory");
+	else
+		ifactory = syl_plugin_lookup_symbol("main_window_menu_factory");
+
+	return ifactory;
+}
+
+gint syl_plugin_add_menuitem(const gchar *parent, const gchar *label,
+			     SylPluginCallbackFunc func, gpointer data)
+{
+	GtkItemFactory *ifactory;
+	GtkWidget *menu;
+	GtkWidget *menuitem;
+
+	if (!parent)
+		return -1;
+
+	ifactory = get_item_factory(parent);
+	if (!ifactory)
+		return -1;
+
+	menu = gtk_item_factory_get_widget(ifactory, parent);
+	if (!menu)
+		return -1;
+
+	if (label)
+		menuitem = gtk_menu_item_new_with_label(label);
+	else {
+		menuitem = gtk_menu_item_new();
+		gtk_widget_set_sensitive(menuitem, FALSE);
+	}
+	gtk_widget_show(menuitem);
+	gtk_menu_append(GTK_MENU(menu), menuitem);
+	if (func)
+		g_signal_connect(G_OBJECT(menuitem), "activate",
+				 G_CALLBACK(func), data);
+
+	return 0;
+}
+
+gint syl_plugin_add_factory_item(const gchar *parent, const gchar *label,
+				 SylPluginCallbackFunc func, gpointer data)
+{
+	GtkItemFactory *ifactory;
+	GtkItemFactoryEntry entry = {NULL, NULL, NULL, 0, NULL};
+
+	if (!parent)
+		return -1;
+
+	ifactory = get_item_factory(parent);
+	if (!ifactory)
+		return -1;
+
+	if (label) {
+		entry.path = (gchar *)label;
+		if (g_str_has_suffix(label, "/---"))
+			entry.item_type = "<Separator>";
+		else
+			entry.item_type = NULL;
+	} else {
+		entry.path = "/---";
+		entry.item_type = "<Separator>";
+	}
+	entry.callback = func;
+	g_print("entry.path = %s\n", entry.path);
+
+	gtk_item_factory_create_item(ifactory, &entry, data, 2);
+
+	return 0;
+}
+
+void syl_plugin_menu_set_sensitive(const gchar *path, gboolean sensitive)
+{
+	GtkItemFactory *ifactory;
+	GtkWidget *widget;
+
+	g_return_if_fail(path != NULL);
+
+	ifactory = get_item_factory(path);
+	if (!ifactory)
+		return;
+
+	widget = gtk_item_factory_get_item(ifactory, path);
+	gtk_widget_set_sensitive(widget, sensitive);
+}
+
+void syl_plugin_menu_set_sensitive_all(GtkMenuShell *menu_shell,
+				       gboolean sensitive)
+{
+	GList *cur;
+
+	for (cur = menu_shell->children; cur != NULL; cur = cur->next)
+		gtk_widget_set_sensitive(GTK_WIDGET(cur->data), sensitive);
+}
+
+void syl_plugin_menu_set_active(const gchar *path, gboolean is_active)
+{
+	GtkItemFactory *ifactory;
+	GtkWidget *widget;
+
+	g_return_if_fail(path != NULL);
+
+	ifactory = get_item_factory(path);
+	if (!ifactory)
+		return;
+
+	widget = gtk_item_factory_get_item(ifactory, path);
+	gtk_check_menu_item_set_active(GTK_CHECK_MENU_ITEM(widget), is_active);
+}
+
+gpointer syl_plugin_folderview_get(void)
+{
+	gpointer sym;
+
+	sym = syl_plugin_lookup_symbol("folderview");
+	return sym;
+}
+
+FolderItem *syl_plugin_folderview_get_selected_item(void)
+{
+	FolderItem * (*func)(gpointer);
+	gpointer folderview;
+
+	folderview = syl_plugin_folderview_get();
+	if (folderview) {
+		func = syl_plugin_lookup_symbol("folderview_get_selected_item");
+		return SAFE_CALL_ARG1_RET(func, folderview);
+	}
+
+	return NULL;
+}
+
+gpointer syl_plugin_summary_view_get(void)
+{
+	gpointer sym;
+
+	sym = syl_plugin_lookup_symbol("summaryview");
+	return sym;
+}
+
+void syl_plugin_sumary_select_by_msgnum(guint msgnum)
+{
+	void (*func)(gpointer, guint);
+	gpointer summary;
+
+	summary = syl_plugin_summary_view_get();
+	if (summary) {
+		func = syl_plugin_lookup_symbol("summary_select_by_msgnum");
+		SAFE_CALL_ARG2(func, summary, msgnum);
+	}
+}
+
+gboolean syl_plugin_summary_select_by_msginfo(MsgInfo *msginfo)
+{
+	gboolean (*func)(gpointer, MsgInfo *);
+	gpointer summary;
+
+	summary = syl_plugin_summary_view_get();
+	if (summary) {
+		func = syl_plugin_lookup_symbol("summary_select_by_msginfo");
+		return SAFE_CALL_ARG2_RET_VAL(func, summary, msginfo, FALSE);
+	}
+
+	return FALSE;
+}
+
+void syl_plugin_open_message(const gchar *folder_id, guint msgnum)
+{
+	FolderItem *item;
+	MsgInfo *msginfo;
+
+	item = folder_find_item_from_identifier(folder_id);
+	msginfo = folder_item_get_msginfo(item, msgnum);
+
+	if (msginfo) {
+		if (!syl_plugin_summary_select_by_msginfo(msginfo)) {
+			syl_plugin_open_message_by_new_window(msginfo);
+		}
+		procmsg_msginfo_free(msginfo);
+	}
+}
+
+gpointer syl_plugin_messageview_create_with_new_window(void)
+{
+	gpointer (*func)(void);
+
+	func = syl_plugin_lookup_symbol("messageview_create_with_new_window");
+	return SAFE_CALL_RET(func);
+}
+
+void syl_plugin_open_message_by_new_window(MsgInfo *msginfo)
+{
+	gpointer msgview;
+	gpointer (*func)(gpointer, MsgInfo *, gboolean);
+
+	msgview = syl_plugin_messageview_create_with_new_window();
+	if (msgview) {
+		func = syl_plugin_lookup_symbol("messageview_show");
+		SAFE_CALL_ARG3(func, msgview, msginfo, FALSE);
+	}
+}
+
+FolderItem *syl_plugin_folder_sel(Folder *cur_folder, gint sel_type,
+				  const gchar *default_folder)
+{
+	FolderItem * (*func)(Folder *, gint, const gchar *);
+
+	func = syl_plugin_lookup_symbol("foldersel_folder_sel");
+	return SAFE_CALL_ARG3_RET(func, cur_folder, sel_type, default_folder);
+}
+
+FolderItem *syl_plugin_folder_sel_full(Folder *cur_folder, gint sel_type,
+				       const gchar *default_folder,
+				       const gchar *message)
+{
+	FolderItem * (*func)(Folder *, gint, const gchar *, const gchar *);
+
+	func = syl_plugin_lookup_symbol("foldersel_folder_sel_full");
+	return SAFE_CALL_ARG4_RET(func, cur_folder, sel_type, default_folder,
+				  message);
+}
+
+gchar *syl_plugin_input_dialog(const gchar *title, const gchar *message,
+			       const gchar *default_string)
+{
+	gchar * (*func)(const gchar *, const gchar *, const gchar *);
+
+	func = syl_plugin_lookup_symbol("input_dialog");
+	return SAFE_CALL_ARG3_RET(func, title, message, default_string);
+}
+
+gchar *syl_plugin_input_dialog_with_invisible(const gchar *title,
+					      const gchar *message,
+					      const gchar *default_string)
+{
+	gchar * (*func)(const gchar *, const gchar *, const gchar *);
+
+	func = syl_plugin_lookup_symbol("input_dialog_with_invisible");
+	return SAFE_CALL_ARG3_RET(func, title, message, default_string);
+}
+
+void syl_plugin_manage_window_set_transient(GtkWindow *window)
+{
+	void (*func)(GtkWindow *);
+
+	func = syl_plugin_lookup_symbol("manage_window_set_transient");
+	SAFE_CALL_ARG1(func, window);
+}
+
+void syl_plugin_manage_window_signals_connect(GtkWindow *window)
+{
+	void (*func)(GtkWindow *);
+
+	func = syl_plugin_lookup_symbol("manage_window_signals_connect");
+	SAFE_CALL_ARG1(func, window);
+}
+
+GtkWidget *syl_plugin_manage_window_get_focus_window(void)
+{
+	GtkWidget * (*func)(void);
+
+	func = syl_plugin_lookup_symbol("manage_window_get_focus_window");
+	return SAFE_CALL_RET(func);
+}
+
+void syl_plugin_inc_mail(void)
+{
+	void (*func)(gpointer);
+
+	func = syl_plugin_lookup_symbol("inc_mail");
+	SAFE_CALL_ARG1(func, syl_plugin_main_window_get());
+}
+
+void syl_plugin_inc_lock(void)
+{
+	void (*func)(void);
+
+	func = syl_plugin_lookup_symbol("inc_lock");
+	SAFE_CALL(func);
+}
+
+void syl_plugin_inc_unlock(void)
+{
+	void (*func)(void);
+
+	func = syl_plugin_lookup_symbol("inc_unlock");
+	SAFE_CALL(func);
+}
diff --git a/src/plugin.h b/src/plugin.h
new file mode 100644
index 00000000..6a120731
--- /dev/null
+++ b/src/plugin.h
@@ -0,0 +1,175 @@
+/*
+ * Sylpheed -- a GTK+ based, lightweight, and fast e-mail client
+ * Copyright (C) 1999-2009 Hiroyuki Yamamoto
+ *
+ * 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.
+ */
+
+#ifndef __PLUGIN_H__
+#define __PLUGIN_H__
+
+#include <glib.h>
+#include <glib-object.h>
+#include <gmodule.h>
+#include <gtk/gtk.h>
+
+#include "procmsg.h"
+#include "folder.h"
+
+/* SylPlugin object */
+
+#define SYL_TYPE_PLUGIN		(syl_plugin_get_type())
+#define SYL_PLUGIN(obj)		(G_TYPE_CHECK_INSTANCE_CAST((obj), SYL_TYPE_PLUGIN, SylPlugin))
+#define SYL_IS_PLUGIN(obj)	(G_TYPE_CHECK_INSTANCE_CAST((obj), SYL_TYPE_PLUGIN))
+#define SYL_PLUGIN_CLASS(klass)	(G_TYPE_CHECK_CLASS_CAST((klass), SYL_TYPE_PLUGIN, SylPluginClass))
+#define SYL_IS_PLUGIN_CLASS(klass)	(G_TYPE_CHECK_CLASS_TYPE((klass), SYL_TYPE_PLUGIN))
+#define SYL_PLUGIN_GET_CLASS(obj)	(G_TYPE_INSTANCE_GET_CLASS((obj), SYL_TYPE_PLUGIN, SylPluginClass))
+
+typedef struct _SylPlugin	SylPlugin;
+typedef struct _SylPluginClass	SylPluginClass;
+typedef struct _SylPluginInfo	SylPluginInfo;
+
+typedef void (*SylPluginLoadFunc)	(void);
+typedef void (*SylPluginUnloadFunc)	(void);
+typedef void (*SylPluginCallbackFunc)	(void);
+
+#define SYL_PLUGIN_INTERFACE_VERSION	0x0100
+
+struct _SylPlugin
+{
+	GObject parent_instance;
+};
+
+struct _SylPluginClass
+{
+	GObjectClass parent_class;
+
+	void (* plugin_load)	(GObject *obj, GModule *module);
+	void (* plugin_unload)	(GObject *obj, GModule *module);
+	void (* folderview_menu_popup)	(GObject *obj, gpointer ifactory);
+};
+
+struct _SylPluginInfo
+{
+	gchar *name;
+	gchar *version;
+	gchar *author;
+	gchar *description;
+
+	gpointer pad1;
+	gpointer pad2;
+	gpointer pad3;
+	gpointer pad4;
+};
+
+GType syl_plugin_get_type	(void);
+
+void syl_plugin_signal_connect		(const gchar *name, GCallback callback,
+					 gpointer data);
+void syl_plugin_signal_disconnect	(gpointer func, gpointer data);
+void syl_plugin_signal_emit		(const gchar *name, ...);
+
+/* Used by Sylpheed */
+
+gint syl_plugin_init_lib	(void);
+
+gint syl_plugin_load		(const gchar *file);
+gint syl_plugin_load_all	(const gchar *dir);
+void syl_plugin_unload_all	(void);
+
+GSList *syl_plugin_get_module_list	(void);
+SylPluginInfo *syl_plugin_get_info	(GModule *module);
+gboolean syl_plugin_check_version	(GModule *module);
+
+gint syl_plugin_add_symbol	(const gchar *name, gpointer sym);
+
+/* Interfaces which should be implemented by plug-ins
+     void plugin_load(void);
+     void plugin_unload(void);
+     SylPluginInfo *plugin_info(void);
+     gint plugin_interface_version(void);
+ */
+
+/* Plug-in API (used by plug-ins) */
+
+const gchar *syl_plugin_get_prog_version	(void);
+
+gpointer syl_plugin_main_window_get		(void);
+void syl_plugin_main_window_popup		(gpointer mainwin);
+
+void syl_plugin_app_will_exit			(gboolean force);
+
+/* Menu */
+gint syl_plugin_add_menuitem			(const gchar *parent,
+						 const gchar *label,
+						 SylPluginCallbackFunc func,
+						 gpointer data);
+gint syl_plugin_add_factory_item		(const gchar *menu,
+						 const gchar *label,
+						 SylPluginCallbackFunc func,
+						 gpointer data);
+
+void syl_plugin_menu_set_sensitive		(const gchar	*path,
+						 gboolean	 sensitive);
+void syl_plugin_menu_set_sensitive_all		(GtkMenuShell	*menu_shell,
+						 gboolean	 sensitive);
+void syl_plugin_menu_set_active			(const gchar	*path,
+						 gboolean	 is_active);
+
+
+/* FolderView */
+gpointer syl_plugin_folderview_get		(void);
+FolderItem *syl_plugin_folderview_get_selected_item
+						(void);
+
+/* SummaryView */
+gpointer syl_plugin_summary_view_get		(void);
+void syl_plugin_sumary_select_by_msgnum		(guint msgnum);
+gboolean syl_plugin_summary_select_by_msginfo	(MsgInfo *msginfo);
+
+void syl_plugin_open_message			(const gchar *folder_id,
+						 guint msgnum);
+
+/* MessageView */
+gpointer syl_plugin_messageview_create_with_new_window
+						(void);
+void syl_plugin_open_message_by_new_window	(MsgInfo *msginfo);
+
+/* Others */
+FolderItem *syl_plugin_folder_sel		(Folder *cur_folder,
+						 gint sel_type,
+						 const gchar *default_folder);
+FolderItem *syl_plugin_folder_sel_full		(Folder *cur_folder,
+						 gint sel_type,
+						 const gchar *default_folder,
+						 const gchar *message);
+
+gchar *syl_plugin_input_dialog			(const gchar *title,
+						 const gchar *message,
+						 const gchar *default_string);
+gchar *syl_plugin_input_dialog_with_invisible	(const gchar *title,
+						 const gchar *message,
+						 const gchar *default_string);
+
+void syl_plugin_manage_window_set_transient	(GtkWindow *window);
+void syl_plugin_manage_window_signals_connect	(GtkWindow *window);
+GtkWidget *syl_plugin_manage_window_get_focus_window
+						(void);
+
+void syl_plugin_inc_mail			(void);
+void syl_plugin_inc_lock			(void);
+void syl_plugin_inc_unlock			(void);
+
+#endif /* __PLUGIN_H__ */
diff --git a/src/plugin_manager.c b/src/plugin_manager.c
new file mode 100644
index 00000000..53195fe9
--- /dev/null
+++ b/src/plugin_manager.c
@@ -0,0 +1,227 @@
+/*
+ * Sylpheed -- a GTK+ based, lightweight, and fast e-mail client
+ * Copyright (C) 1999-2009 Hiroyuki Yamamoto
+ *
+ * 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.
+ */
+
+#ifdef HAVE_CONFIG_H
+#  include "config.h"
+#endif
+
+#include "defs.h"
+
+#include <glib.h>
+#include <glib/gi18n.h>
+#include <gdk/gdkkeysyms.h>
+#include <gtk/gtk.h>
+
+#include "plugin.h"
+#include "plugin_manager.h"
+#include "manage_window.h"
+#include "gtkutils.h"
+
+static struct PluginManagerWindow {
+	GtkWidget *window;
+	GtkWidget *close_btn;
+
+	GtkWidget *treeview;
+	GtkListStore *store;
+	GtkTreeSelection *selection;
+} pm_window;
+
+enum {
+	COL_INFO,
+	N_COLS
+};
+
+static void plugin_manager_create	(void);
+static void plugin_manager_set_list_row	(GtkTreeIter	*iter,
+					 SylPluginInfo	*info,
+					 const gchar	*filename);
+static gint plugin_manager_deleted	(GtkWidget	*widget,
+					 GdkEventAny	*event,
+					 gpointer	 data);
+static gboolean key_pressed		(GtkWidget	*widget,
+					 GdkEventKey	*event,
+					 gpointer	 data);
+
+void plugin_manager_open(void)
+{
+	GSList *list, *cur;
+	SylPluginInfo *info;
+	GModule *module;
+	const gchar *filename;
+
+	if (!pm_window.window)
+		plugin_manager_create();
+	else
+		gtk_window_present(GTK_WINDOW(pm_window.window));
+
+	list = syl_plugin_get_module_list();
+
+	gtk_list_store_clear(pm_window.store);
+
+	for (cur = list; cur != NULL; cur = cur->next) {
+		module = (GModule *)cur->data;
+
+		filename = g_module_name(module);
+		info = syl_plugin_get_info(module);
+		if (info) {
+			debug_print("------------------------------\n");
+			debug_print("filename      : %s\n", filename);
+			debug_print("plugin name   : %s\n", info->name);
+			debug_print("plugin version: %s\n", info->version);
+			debug_print("plugin author : %s\n", info->author);
+			debug_print("description   : %s\n", info->description ? info->description : "");
+			debug_print("------------------------------\n");
+			plugin_manager_set_list_row(NULL, info, filename);
+		} else {
+			debug_print("info not found: %s\n", filename);
+		}
+	}
+
+	gtk_widget_show(pm_window.window);
+	manage_window_focus_in(pm_window.window, NULL, NULL);
+}
+
+static void plugin_manager_create(void)
+{
+	GtkWidget *window;
+	GtkWidget *vbox;
+	GtkWidget *close_btn;
+	GtkWidget *confirm_area;
+
+	GtkWidget *scrolledwin;
+	GtkWidget *treeview;
+	GtkListStore *store;
+	GtkTreeSelection *selection;
+	GtkTreeViewColumn *column;
+	GtkCellRenderer *renderer;
+
+	window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
+	gtk_window_set_title(GTK_WINDOW(window), _("Plug-in manager"));
+	gtk_widget_set_size_request(window, 600, 400);
+	gtk_window_set_policy(GTK_WINDOW(window), FALSE, TRUE, TRUE);
+	gtk_container_set_border_width(GTK_CONTAINER(window), 8);
+
+	vbox = gtk_vbox_new(FALSE, 6);
+	gtk_widget_show(vbox);
+	gtk_container_add(GTK_CONTAINER(window), vbox);
+
+	gtkut_stock_button_set_create(&confirm_area,
+				      &close_btn, GTK_STOCK_CLOSE,
+				      NULL, NULL, NULL, NULL);
+	gtk_widget_show(confirm_area);
+	gtk_box_pack_end(GTK_BOX(vbox), confirm_area, FALSE, FALSE, 0);
+	gtk_widget_grab_default(close_btn);
+
+	g_signal_connect(G_OBJECT(window), "delete_event",
+			 G_CALLBACK(plugin_manager_deleted), NULL);
+	g_signal_connect(G_OBJECT(window), "key_press_event",
+			 G_CALLBACK(key_pressed), NULL);
+	g_signal_connect(G_OBJECT(close_btn), "clicked",
+			 G_CALLBACK(plugin_manager_deleted), NULL);
+
+	scrolledwin = gtk_scrolled_window_new(NULL, NULL);
+	gtk_widget_show(scrolledwin);
+	gtk_widget_set_size_request(scrolledwin, -1, -1);
+	gtk_box_pack_start(GTK_BOX(vbox), scrolledwin, TRUE, TRUE, 0);
+	gtk_scrolled_window_set_policy(GTK_SCROLLED_WINDOW(scrolledwin),
+				       GTK_POLICY_AUTOMATIC,
+				       GTK_POLICY_AUTOMATIC);
+	gtk_scrolled_window_set_shadow_type(GTK_SCROLLED_WINDOW(scrolledwin),
+					    GTK_SHADOW_IN);
+
+	store = gtk_list_store_new(N_COLS, G_TYPE_STRING);
+
+	treeview = gtk_tree_view_new_with_model(GTK_TREE_MODEL(store));
+	g_object_unref(G_OBJECT(store));
+	gtk_tree_view_set_headers_visible(GTK_TREE_VIEW(treeview), TRUE);
+	gtk_tree_view_set_rules_hint(GTK_TREE_VIEW(treeview), TRUE);
+	gtk_tree_view_set_search_column(GTK_TREE_VIEW(treeview), COL_INFO);
+#if GTK_CHECK_VERSION(2, 10, 0)
+	gtk_tree_view_set_grid_lines(GTK_TREE_VIEW(treeview),
+				     GTK_TREE_VIEW_GRID_LINES_HORIZONTAL);
+#endif
+
+	selection = gtk_tree_view_get_selection(GTK_TREE_VIEW(treeview));
+	gtk_tree_selection_set_mode(selection, GTK_SELECTION_BROWSE);
+
+	renderer = gtk_cell_renderer_text_new();
+	column = gtk_tree_view_column_new_with_attributes
+		(_("Plug-in information"), renderer, "text", COL_INFO, NULL);
+	gtk_tree_view_column_set_sizing(column, GTK_TREE_VIEW_COLUMN_AUTOSIZE);
+	gtk_tree_view_append_column(GTK_TREE_VIEW(treeview), column);
+
+	gtk_widget_show(treeview);
+	gtk_container_add(GTK_CONTAINER(scrolledwin), treeview);
+
+	gtk_widget_show_all(window);
+
+	pm_window.window = window;
+	pm_window.close_btn = close_btn;
+
+	pm_window.treeview = treeview;
+	pm_window.store = store;
+	pm_window.selection = selection;
+}
+
+static void plugin_manager_set_list_row(GtkTreeIter *iter, SylPluginInfo *info,
+					const gchar *filename)
+{
+	GtkListStore *store = pm_window.store;
+	GtkTreeIter iter_;
+	gchar *plugin_info;
+
+	g_return_if_fail(info != NULL);
+	g_return_if_fail(filename != NULL);
+
+	plugin_info = g_strconcat(info->name ? info->name : _("(Unknown)"),
+				  "  ", info->version ? info->version : "", "\n",
+				  _("Author: "), info->author ? info->author : _("(Unknown)"), "\n",
+				  _("File: "), filename ? filename : _("(Unknown)"),
+				  info->description ? "\n" : "",
+				  info->description ? _("Description: ") : "",
+				  info->description ? info->description : "",
+				  NULL);
+
+	if (iter)
+		iter_ = *iter;
+	else
+		gtk_list_store_append(store, &iter_);
+
+	gtk_list_store_set(store, &iter_, COL_INFO, plugin_info, -1);
+
+	g_free(plugin_info);
+}
+
+static gint plugin_manager_deleted(GtkWidget *widget, GdkEventAny *event,
+				   gpointer data)
+{
+	gtk_widget_hide(pm_window.window);
+	return TRUE;
+}
+
+static gboolean key_pressed(GtkWidget *widget, GdkEventKey *event,
+			    gpointer data)
+{
+	if (event && event->keyval == GDK_Escape) {
+		gtk_widget_hide(pm_window.window);
+		return TRUE;
+	}
+
+	return FALSE;
+}
diff --git a/src/plugin_manager.h b/src/plugin_manager.h
new file mode 100644
index 00000000..c139de2f
--- /dev/null
+++ b/src/plugin_manager.h
@@ -0,0 +1,29 @@
+/*
+ * Sylpheed -- a GTK+ based, lightweight, and fast e-mail client
+ * Copyright (C) 1999-2009 Hiroyuki Yamamoto
+ *
+ * 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.
+ */
+
+#ifndef __PLUGIN_MANAGER_H__
+#define __PLUGIN_MANAGER_H__
+
+#ifdef HAVE_CONFIG_H
+#  include "config.h"
+#endif
+
+void plugin_manager_open(void);
+
+#endif /* __PLUGIN_MANAGER_H__ */
diff --git a/src/prefs_common_dialog.c b/src/prefs_common_dialog.c
index eeedc28b..88da4d17 100644
--- a/src/prefs_common_dialog.c
+++ b/src/prefs_common_dialog.c
@@ -1,6 +1,6 @@
 /*
  * Sylpheed -- a GTK+ based, lightweight, and fast e-mail client
- * Copyright (C) 1999-2008 Hiroyuki Yamamoto
+ * Copyright (C) 1999-2009 Hiroyuki Yamamoto
  *
  * 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
@@ -233,6 +233,12 @@ static struct Extcmd {
 	GtkWidget *button_extsend;
 } extcmd;
 
+static struct UpdateCheck {
+	GtkWidget *checkbtn_autoupdate;
+	GtkWidget *checkbtn_useproxy;
+	GtkWidget *entry_proxyhost;
+} update_check;
+
 static struct Advanced {
 	GtkWidget *checkbtn_strict_cache_check;
 
@@ -540,6 +546,14 @@ static PrefsUIData ui_data[] = {
 	{"ext_sendmail_cmd", &extcmd.entry_extsend,
 	 prefs_set_data_from_entry, prefs_set_entry},
 
+	/* Update check */
+	{"auto_update_check", &update_check.checkbtn_autoupdate,
+	 prefs_set_data_from_toggle, prefs_set_toggle},
+	{"use_http_proxy", &update_check.checkbtn_useproxy,
+	 prefs_set_data_from_toggle, prefs_set_toggle},
+	{"http_proxy_host", &update_check.entry_proxyhost,
+	 prefs_set_data_from_entry, prefs_set_entry},
+
 	/* Advanced */
 	{"strict_cache_check", &advanced.checkbtn_strict_cache_check,
 	 prefs_set_data_from_toggle, prefs_set_toggle},
@@ -567,6 +581,7 @@ static void prefs_privacy_create	(void);
 static void prefs_details_create	(void);
 static GtkWidget *prefs_other_create	(void);
 static GtkWidget *prefs_extcmd_create	(void);
+static GtkWidget *prefs_update_create	(void);
 static GtkWidget *prefs_advanced_create	(void);
 
 static void prefs_common_set_encoding_optmenu	(GtkOptionMenu	*optmenu,
@@ -2168,6 +2183,7 @@ static void prefs_details_create(void)
 
 	GtkWidget *other_wid;
 	GtkWidget *extcmd_wid;
+	GtkWidget *update_wid;
 	GtkWidget *advanced_wid;
 
 	vbox1 = gtk_vbox_new (FALSE, VSPACING);
@@ -2268,6 +2284,10 @@ static void prefs_details_create(void)
 	extcmd_wid = prefs_extcmd_create();
 	gtk_box_pack_start(GTK_BOX(vbox_tab), extcmd_wid, FALSE, FALSE, 0);
 
+	APPEND_SUB_NOTEBOOK(notebook, vbox_tab, _("Update"));
+	update_wid = prefs_update_create();
+	gtk_box_pack_start(GTK_BOX(vbox_tab), update_wid, FALSE, FALSE, 0);
+
 	APPEND_SUB_NOTEBOOK(notebook, vbox_tab, _("Advanced"));
 	advanced_wid = prefs_advanced_create();
 	gtk_box_pack_start(GTK_BOX(vbox_tab), advanced_wid, FALSE, FALSE, 0);
@@ -2581,6 +2601,53 @@ static GtkWidget *prefs_extcmd_create(void)
 	return vbox1;
 }
 
+static GtkWidget *prefs_update_create(void)
+{
+	GtkWidget *vbox1;
+	GtkWidget *vbox2;
+	GtkWidget *checkbtn_autoupdate;
+	GtkWidget *checkbtn_useproxy;
+	GtkWidget *label;
+	GtkWidget *entry_proxyhost;
+
+	vbox1 = gtk_vbox_new (FALSE, VSPACING);
+	gtk_widget_show (vbox1);
+
+#ifndef G_OS_WIN32
+	label = gtk_label_new (_("Update check requires 'curl' command."));
+	gtk_widget_show (label);
+	gtk_misc_set_alignment (GTK_MISC (label), 0, 0.5);
+	gtk_box_pack_start (GTK_BOX (vbox1), label, FALSE, FALSE, 0);
+#endif
+
+	vbox2 = gtk_vbox_new (FALSE, VSPACING_NARROW);
+	gtk_widget_show (vbox2);
+	gtk_box_pack_start (GTK_BOX (vbox1), vbox2, FALSE, FALSE, 0);
+
+	PACK_CHECK_BUTTON (vbox2, checkbtn_autoupdate,
+			   _("Enable auto update check"));
+	PACK_CHECK_BUTTON (vbox2, checkbtn_useproxy,
+			   _("Use HTTP proxy"));
+
+	label = gtk_label_new (_("HTTP proxy host (hostname:port):"));
+	gtk_widget_show (label);
+	gtk_misc_set_alignment (GTK_MISC (label), 0, 0.5);
+	gtk_box_pack_start (GTK_BOX (vbox2), label, FALSE, FALSE, 0);
+
+	entry_proxyhost = gtk_entry_new ();
+	gtk_widget_show (entry_proxyhost);
+	gtk_box_pack_start (GTK_BOX (vbox2), entry_proxyhost, FALSE, FALSE, 0);
+
+	SET_TOGGLE_SENSITIVITY(checkbtn_useproxy, label);
+	SET_TOGGLE_SENSITIVITY(checkbtn_useproxy, entry_proxyhost);
+
+	update_check.checkbtn_autoupdate = checkbtn_autoupdate;
+	update_check.checkbtn_useproxy = checkbtn_useproxy;
+	update_check.entry_proxyhost = entry_proxyhost;
+
+	return vbox1;
+}
+
 static GtkWidget *prefs_advanced_create(void)
 {
 	GtkWidget *vbox1;
diff --git a/src/update_check.c b/src/update_check.c
new file mode 100644
index 00000000..5979ea5f
--- /dev/null
+++ b/src/update_check.c
@@ -0,0 +1,255 @@
+/*
+ * Sylpheed -- a GTK+ based, lightweight, and fast e-mail client
+ * Copyright (C) 1999-2009 Hiroyuki Yamamoto
+ *
+ * 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.
+ */
+
+#ifdef HAVE_CONFIG_H
+#  include "config.h"
+#endif
+
+#include "defs.h"
+
+#include <glib.h>
+#include <glib/gi18n.h>
+#include <gdk/gdkkeysyms.h>
+#include <gtk/gtk.h>
+
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "update_check.h"
+#include "manage_window.h"
+#include "gtkutils.h"
+#include "alertpanel.h"
+#include "prefs_common.h"
+#include "socket.h"
+#include "utils.h"
+#include "version.h"
+
+
+static gboolean compare_version(gint major, gint minor, gint micro,
+				const gchar *extra)
+{
+	debug_print("comparing %d.%d.%d.%s <> " VERSION "\n", major, minor, micro, extra ? extra : "");
+
+	if (major > MAJOR_VERSION)
+		return TRUE;
+	if (major < MAJOR_VERSION)
+		return FALSE;
+	if (minor > MINOR_VERSION)
+		return TRUE;
+	if (minor < MINOR_VERSION)
+		return FALSE;
+	if (micro > MICRO_VERSION)
+		return TRUE;
+	if (micro < MICRO_VERSION)
+		return FALSE;
+	if (extra) {
+		if (strcmp(extra, EXTRA_VERSION) > 0)
+			return TRUE;
+	}
+
+	return FALSE;
+}
+
+static void parse_version_string(const gchar *ver, gint *major, gint *minor,
+				 gint *micro, gchar **extra)
+{
+	gchar **vers;
+
+	vers = g_strsplit(ver, ".", -1);
+	if (vers[0]) {
+		*major = atoi(vers[0]);
+		if (vers[1]) {
+			*minor = atoi(vers[1]);
+			if (vers[2]) {
+				*micro = atoi(vers[2]);
+				if (vers[3]) {
+					*extra = g_strdup(vers[3]);
+				}
+			}
+		}
+	}
+	g_strfreev(vers);
+}
+
+static void update_dialog(const gchar *new_ver, gboolean manual)
+{
+	gchar buf[1024];
+	AlertValue val;
+
+	if (new_ver)
+		g_snprintf(buf, sizeof(buf), "%s\n\n%s -> %s",
+			   _("The newer version of Sylpheed found.\n"
+			     "Upgrade now?"),
+			   VERSION, new_ver);
+	else
+		g_snprintf(buf, sizeof(buf), "%s",
+			   _("The newer version of Sylpheed found.\n"
+			     "Upgrade now?"));
+
+	val = alertpanel_full(_("New version found"), buf,
+			      ALERT_QUESTION,
+			      G_ALERTDEFAULT,
+			      manual ? FALSE : TRUE,
+			      GTK_STOCK_YES, GTK_STOCK_NO, NULL);
+	if ((val & G_ALERT_VALUE_MASK) == G_ALERTDEFAULT) {
+		open_uri(HOMEPAGE_URI, prefs_common.uri_cmd);
+	}
+	if (val & G_ALERTDISABLE) {
+		prefs_common.auto_update_check = FALSE;
+	}
+}
+
+static gint child_stdout;
+
+static void update_check_cb(GPid pid, gint status, gpointer data)
+{
+	gchar **lines;
+	gchar *key, *val, *p;
+	gchar *new_ver = NULL;
+	gint i;
+#ifdef DEVEL_VERSION
+	gboolean cur_ver_is_release = FALSE;
+#else
+	gboolean cur_ver_is_release = TRUE;
+#endif
+	gboolean result = FALSE;
+	gboolean got_version = FALSE;
+	gboolean show_dialog_always = (gboolean)data;
+	gchar buf[BUFFSIZE];
+	ssize_t size;
+
+	debug_print("update_check_cb\n");
+
+	if (!child_stdout) {
+		g_spawn_close_pid(pid);
+		return;
+	}
+
+	size = read(child_stdout, buf, sizeof(buf) - 1);
+	if (size < 0) {
+		fd_close(child_stdout);
+		child_stdout = 0;
+		g_spawn_close_pid(pid);
+		return;
+	}
+	buf[size] = '\0';
+
+	fd_close(child_stdout);
+	child_stdout = 0;
+	g_spawn_close_pid(pid);
+
+	lines = g_strsplit(buf, "\n", -1);
+
+	for (i = 0; lines[i] != NULL; i++) {
+		gint major = 0, minor = 0, micro = 0;
+		gchar *extra = NULL;
+
+		debug_print("update_check: %s\n", lines[i]);
+		p = strchr(lines[i], '=');
+		if (!p) continue;
+		key = g_strndup(lines[i], p - lines[i]);
+		val = p + 1;
+
+		if (!strcmp(key, "RELEASE")) {
+			parse_version_string(val, &major, &minor, &micro,
+					     &extra);
+			result = compare_version(major, minor, micro, extra);
+		} else if (!cur_ver_is_release && !strcmp(key, "DEVEL")) {
+			parse_version_string(val, &major, &minor, &micro,
+					     &extra);
+			result = compare_version(major, minor, micro, extra);
+		}
+
+		if (major + minor + micro != 0)
+			got_version = TRUE;
+
+		if (result) {
+			new_ver = g_strdup_printf("%d.%d.%d%s", major, minor, micro, extra ? extra : "");
+			debug_print("update_check: new ver: %s\n", new_ver);
+			g_free(extra);
+			g_free(key);
+			break;
+		}
+		g_free(extra);
+		g_free(key);
+	}
+
+	g_strfreev(lines);
+
+	if (result)
+		update_dialog(new_ver, show_dialog_always);
+	else if (show_dialog_always) {
+		if (got_version)
+			alertpanel_message(_("Information"),
+					   _("Sylpheed is already the latest version."),
+					   ALERT_NOTICE);
+		else
+			alertpanel_error(_("Couldn't get the version information."));
+	}
+	g_free(new_ver);
+}
+
+void update_check(gboolean show_dialog_always)
+{
+	gchar *cmdline[6] = {"curl", "--silent"};
+	GPid pid;
+	GError *error = NULL;
+
+	if (child_stdout > 0) {
+		debug_print("update check is in progress\n");
+		return;
+	}
+
+	child_stdout = 0;
+
+	debug_print("update_check: getting latest version from http://sylpheed.sraoss.jp/version.txt\n");
+
+	cmdline[2] = "http://sylpheed.sraoss.jp/version.txt?";
+	if (prefs_common.use_http_proxy && prefs_common.http_proxy_host &&
+	    prefs_common.http_proxy_host[0] != '\0') {
+		cmdline[3] = "--proxy";
+		cmdline[4] = prefs_common.http_proxy_host;
+		cmdline[5] = NULL;
+	} else
+		cmdline[3] = NULL;
+
+	if (g_spawn_async_with_pipes
+		(NULL, cmdline, NULL,
+		 G_SPAWN_DO_NOT_REAP_CHILD | G_SPAWN_SEARCH_PATH,
+		 NULL, NULL, &pid,
+		 NULL, &child_stdout, NULL, &error) == FALSE) {
+		g_warning("Couldn't execute curl");
+		if (error) {
+			g_warning("g_spawn_async_with_pipes: %s",
+				  error->message);
+			g_error_free(error);
+		}
+		return;
+	}
+	if (pid == 0) {
+		g_warning("Couldn't get PID of child process");
+		if (child_stdout) {
+			fd_close(child_stdout);
+			child_stdout = 0;
+		}
+		return;
+	}
+
+	g_child_watch_add(pid, update_check_cb, (gpointer)show_dialog_always);
+}
diff --git a/src/update_check.h b/src/update_check.h
new file mode 100644
index 00000000..532a407a
--- /dev/null
+++ b/src/update_check.h
@@ -0,0 +1,29 @@
+/*
+ * Sylpheed -- a GTK+ based, lightweight, and fast e-mail client
+ * Copyright (C) 1999-2009 Hiroyuki Yamamoto
+ *
+ * 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.
+ */
+
+#ifndef __UPDATE_CHECK_H__
+#define __UPDATE_CHECK_H__
+
+#ifdef HAVE_CONFIG_H
+#  include "config.h"
+#endif
+
+void update_check(gboolean show_dialog_always);
+
+#endif /* __PLUGIN_MANAGER_H__ */
diff --git a/src/version.h.in b/src/version.h.in
index d7fac0aa..8e7affa6 100644
--- a/src/version.h.in
+++ b/src/version.h.in
@@ -1,6 +1,6 @@
 /*
  * Sylpheed -- a GTK+ based, lightweight, and fast e-mail client
- * Copyright (C) 1999-2006 Hiroyuki Yamamoto
+ * Copyright (C) 1999-2009 Hiroyuki Yamamoto
  *
  * 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
@@ -22,6 +22,10 @@
 
 #define PACKAGE			"@PACKAGE@"
 #define VERSION			"@VERSION@"
+#define MAJOR_VERSION		@MAJOR_VERSION@
+#define MINOR_VERSION		@MINOR_VERSION@
+#define MICRO_VERSION		@MICRO_VERSION@
+#define EXTRA_VERSION		"@EXTRA_VERSION@"
 #define PROG_VERSION		"Sylpheed " VERSION
 
 #endif /* __VERSION_H__ */