Plugin architecture for Gnumeric by Tom Dyas 1998-09-10 Tom Dyas <tdyas@romulus.rutgers.edu>

	* src/func.c: Made install_symbols public.

	* src/main.c: initialize the plugins.

	* src/workbook.c (plugins_cmd): Add a menu option for plugin
	loading.

	* plugin-manager.c: New file.  Implements the GUI part of the
	plugin manager.

	* plugin.c, plugin.h: New file. Support for the dynamically loaded
	Gnumeric plugin components.

ChangeLog-1999-07-09

+1998-09-10  Tom Dyas <tdyas@romulus.rutgers.edu>
+
+	* src/func.c: Made install_symbols public.
+
+	* src/main.c: initialize the plugins.
+
+	* src/workbook.c (plugins_cmd): Add a menu option for plugin
+	loading.
+
+	* plugin-manager.c: New file.  Implements the GUI part of the
+	plugin manager.
+
+	* plugin.c, plugin.h: New file. Support for the dynamically loaded
+	Gnumeric plugin components.
+
+	
 1998-09-10  Miguel de Icaza  <miguel@nuclecu.unam.mx>
 
 	* src/dialog-cell-format.c (dialog_cell_format): save and restore

ChangeLog-2000-02-23

+1998-09-10  Tom Dyas <tdyas@romulus.rutgers.edu>
+
+	* src/func.c: Made install_symbols public.
+
+	* src/main.c: initialize the plugins.
+
+	* src/workbook.c (plugins_cmd): Add a menu option for plugin
+	loading.
+
+	* plugin-manager.c: New file.  Implements the GUI part of the
+	plugin manager.
+
+	* plugin.c, plugin.h: New file. Support for the dynamically loaded
+	Gnumeric plugin components.
+
+	
 1998-09-10  Miguel de Icaza  <miguel@nuclecu.unam.mx>
 
 	* src/dialog-cell-format.c (dialog_cell_format): save and restore

Makefile.am

-SUBDIRS = intl po macros src
\ No newline at end of file
+SUBDIRS = intl po macros src

OChangeLog-1999-07-09

+1998-09-10  Tom Dyas <tdyas@romulus.rutgers.edu>
+
+	* src/func.c: Made install_symbols public.
+
+	* src/main.c: initialize the plugins.
+
+	* src/workbook.c (plugins_cmd): Add a menu option for plugin
+	loading.
+
+	* plugin-manager.c: New file.  Implements the GUI part of the
+	plugin manager.
+
+	* plugin.c, plugin.h: New file. Support for the dynamically loaded
+	Gnumeric plugin components.
+
+	
 1998-09-10  Miguel de Icaza  <miguel@nuclecu.unam.mx>
 
 	* src/dialog-cell-format.c (dialog_cell_format): save and restore

OChangeLog-2000-02-23

+1998-09-10  Tom Dyas <tdyas@romulus.rutgers.edu>
+
+	* src/func.c: Made install_symbols public.
+
+	* src/main.c: initialize the plugins.
+
+	* src/workbook.c (plugins_cmd): Add a menu option for plugin
+	loading.
+
+	* plugin-manager.c: New file.  Implements the GUI part of the
+	plugin manager.
+
+	* plugin.c, plugin.h: New file. Support for the dynamically loaded
+	Gnumeric plugin components.
+
+	
 1998-09-10  Miguel de Icaza  <miguel@nuclecu.unam.mx>
 
 	* src/dialog-cell-format.c (dialog_cell_format): save and restore

src/Makefile.am

@@ -54,6 +54,9 @@ GNUMERIC_BASE_SOURCES =			\
 	parser.y			\
 	pattern-selector.c		\
 	pattern-selector.h		\
+	plugin.c			\
+	plugin.h			\
+	plugin-manager.c		\
 	sheet.c				\
 	sheet.h				\
 	sheet-object.c			\

src/func.c

@@ -134,7 +134,7 @@ function_iterate_argument_values (Sheet                   *sheet,
 	return result;
 }
 
-static void
+void
 install_symbols (FunctionDefinition *functions)
 {
 	int i;

src/func.h

@@ -37,5 +37,7 @@ function_iterate_argument_values (Sheet                   *sheet,
 				  char                    **error_string);
 				  
 
+void install_symbols (FunctionDefinition *functions);
+
 #endif /* GNUMERIC_FUNC_H */
 

src/libgnumeric.c

@@ -2,6 +2,7 @@
 #include <gnome.h>
 #include "gnumeric.h"
 #include "xml-io.h"
+#include "plugin.h"
 
 /* If set, the file to load at startup time */
 static char *startup_file;
@@ -42,6 +43,7 @@ main (int argc, char *argv [])
 	symbol_init ();
 	constants_init ();
 	functions_init ();
+	plugins_init ();
 
 	if (startup_file)
 		current_workbook = gnumericReadXmlWorkbook (startup_file);

src/main.c

@@ -2,6 +2,7 @@
 #include <gnome.h>
 #include "gnumeric.h"
 #include "xml-io.h"
+#include "plugin.h"
 
 /* If set, the file to load at startup time */
 static char *startup_file;
@@ -42,6 +43,7 @@ main (int argc, char *argv [])
 	symbol_init ();
 	constants_init ();
 	functions_init ();
+	plugins_init ();
 
 	if (startup_file)
 		current_workbook = gnumericReadXmlWorkbook (startup_file);

src/plugin-manager.c

+/*
+ * plugin-manager.c: Dialog used to load plugins into the Gnumeric
+ * spreadsheet
+ *
+ * Author:
+ *   Tom Dyas (tdyas@romulus.rutgers.edu)
+ */
+#include <glib.h>
+#include <gnome.h>
+#include "gnumeric.h"
+#include "dialogs.h"
+#include "plugin.h"
+
+typedef struct 
+{
+	GtkWidget *dialog;
+	GtkWidget *hbox;
+	GtkWidget *vbbox;
+	GtkWidget *clist;
+	GtkWidget *button_add;
+	GtkWidget *button_remove;
+	GtkWidget *button_close;
+} PluginManager;
+
+static void
+add_to_clist (PluginData *pd, GtkWidget *clist)
+{
+	gchar *data[2];
+	gint row;
+	
+	data [0] = pd->title;
+	data [1] = g_module_name (pd->handle);
+	
+	row = gtk_clist_append (GTK_CLIST (clist), data);
+	gtk_clist_set_row_data (GTK_CLIST (clist), row, pd);
+}
+
+static void
+populate_clist (GtkWidget *clist)
+{
+	gtk_clist_freeze (GTK_CLIST (clist));
+	gtk_clist_clear (GTK_CLIST (clist));
+	g_list_foreach (plugin_list, (GFunc) add_to_clist, clist);
+	gtk_clist_thaw (GTK_CLIST (clist));
+}
+
+static void
+close_cb (GtkWidget *button, PluginManager *pm)
+{
+	gtk_widget_destroy (pm->dialog);
+}
+
+static void
+add_cb (GtkWidget *button, PluginManager *pm)
+{
+	char *modfile = dialog_query_load_file ();
+	PluginData *pd;
+	
+	if (!modfile)
+		return;
+	
+	pd = plugin_load (modfile);
+	populate_clist (pm->clist);
+}
+
+static void
+remove_cb (GtkWidget *button, PluginManager *pm)
+{
+	GList *selection = GTK_CLIST (pm->clist)->selection;
+	gint row = (gint) g_list_nth_data (selection, 0);
+	PluginData *pd = gtk_clist_get_row_data (GTK_CLIST (pm->clist), row);
+	
+	g_print("remove_cb: activated\n");
+	
+	plugin_unload (pd);
+	populate_clist (pm->clist);
+}
+
+static void
+select_row_cb (GtkWidget * clist, gint row, gint col,
+	       GdkEvent *event,  PluginManager *pm)
+{
+	gtk_widget_set_sensitive (pm->button_remove, 1);
+}
+
+static void
+unselect_row_cb (GtkWidget * clist, gint row, gint col,
+		 GdkEvent *event, PluginManager *pm)
+{
+	gtk_widget_set_sensitive (pm->button_remove, 0);
+}
+
+GtkWidget *
+plugin_manager_new (void)
+{
+	PluginManager *pm;
+	gchar *titles[2] = { "Name", "File" };
+	
+	pm = g_new0 (PluginManager, 1);
+	if (!pm)
+		return NULL;
+	
+	pm->dialog = gtk_window_new (GTK_WINDOW_DIALOG);
+	
+	pm->hbox = gtk_hbox_new (0, 0);
+	gtk_container_add (GTK_CONTAINER (pm->dialog), pm->hbox);
+	
+	pm->clist = gtk_clist_new_with_titles (2, titles);
+	gtk_box_pack_start (GTK_BOX (pm->hbox), pm->clist, 1, 1, 5);
+	
+	pm->vbbox = gtk_vbutton_box_new ();
+	gtk_button_box_set_layout (GTK_BUTTON_BOX (pm->vbbox), GTK_BUTTONBOX_START);
+	gtk_box_pack_start (GTK_BOX (pm->hbox), pm->vbbox, 0, 0, 5);
+	
+	pm->button_close = gtk_button_new_with_label ("Close");
+	gtk_container_add (GTK_CONTAINER(pm->vbbox), pm->button_close);
+	
+	pm->button_add = gtk_button_new_with_label ("Add...");
+	gtk_container_add (GTK_CONTAINER (pm->vbbox), pm->button_add);
+	
+	pm->button_remove = gtk_button_new_with_label ("Remove");
+	gtk_container_add (GTK_CONTAINER (pm->vbbox), pm->button_remove);
+	
+	gtk_widget_realize (pm->clist);
+	populate_clist (pm->clist);
+	
+	gtk_signal_connect (GTK_OBJECT (pm->button_close), "clicked",
+			    GTK_SIGNAL_FUNC (close_cb), pm);
+	
+	gtk_signal_connect(GTK_OBJECT (pm->button_add), "clicked",
+			   GTK_SIGNAL_FUNC (add_cb), pm);
+	
+	gtk_signal_connect (GTK_OBJECT (pm->button_remove), "clicked",
+			   GTK_SIGNAL_FUNC (remove_cb), pm);
+	
+	gtk_signal_connect(GTK_OBJECT (pm->clist), "select_row",
+			   GTK_SIGNAL_FUNC (select_row_cb), pm);
+	
+	gtk_signal_connect(GTK_OBJECT (pm->clist), "unselect_row",
+			   GTK_SIGNAL_FUNC (unselect_row_cb), pm);
+	
+	gtk_widget_show_all (pm->hbox);
+	
+	return pm->dialog;
+}

src/plugin.c

+/*
+ * Support for dynamically-loaded Gnumeric plugin components.
+ *
+ * Author:
+ *    Tom Dyas (tdyas@romulus.rutgers.edu)
+ */
+
+#include <unistd.h>
+#include <dirent.h>
+#include <glib.h>
+#include <gmodule.h>
+#include <gnome.h>
+#include <string.h>
+#include "gnumeric.h"
+#include "plugin.h"
+
+GList *plugin_list = NULL;
+
+PluginData *
+plugin_load (gchar *modfile)
+{
+	PluginData *data;
+
+	g_return_val_if_fail (modfile != NULL, NULL);
+	
+	g_print("Loading plugin '%s'.\n", modfile);
+	
+	data = g_new0 (PluginData, 1);
+	if (!data){
+		g_print ("allocation error");
+		return NULL;
+	}
+	
+	data->handle = g_module_open (modfile, 0);
+	if (!data->handle) {
+		g_print ("unable to open module file: %s\n", g_module_error());
+		g_free(data);
+		return NULL;
+	}
+	
+	if (!g_module_symbol (data->handle, "init_plugin", (gpointer *) &data->init_plugin)){
+		g_print ("module must contain init_plugin function");
+		goto error;
+	}
+	
+	if (!g_module_symbol (data->handle, "cleanup_plugin", (gpointer *) &data->cleanup_plugin)){
+		g_print("module must contain cleanup_plugin funciton");
+		goto error;
+	}
+
+	if (data->init_plugin (data) < 0){
+		g_print ("init_plugin returned error");
+		goto error;
+	}
+
+	plugin_list = g_list_append (plugin_list, data);
+	return data;
+
+ error:
+	g_module_close (data->handle);
+	g_free (data);
+	return NULL;
+}
+
+void
+plugin_unload (struct PluginData *pd)
+{
+	g_return_if_fail (pd != NULL);
+	
+	g_print ("unloading plugin %s\n", g_module_name (pd->handle));
+
+	if (pd->refcount > 0) {
+		g_print ("unload_plugin: refcount is positve, cannot unload\n");
+		return;
+	}
+	
+	if (pd->cleanup_plugin)
+		pd->cleanup_plugin (pd);
+
+	plugin_list = g_list_remove (plugin_list, pd);
+
+	g_module_close (pd->handle);
+	g_free (pd);
+	g_print ("unload_plugin: plugin is unloaded\n");
+}
+
+static void
+plugin_load_plugins_in_dir (char *directory)
+{
+	DIR *d;
+	struct dirent *e;
+	
+	if ((d = opendir (directory)) == NULL)
+		return;
+	
+	while ((e = readdir (d)) != NULL){
+		if (strncmp (e->d_name + strlen (e->d_name) - 3, ".so", 3) == 0){
+			char *plugin_name;
+			
+			plugin_name = g_copy_strings (directory, e->d_name, NULL);
+			plugin_load (plugin_name);
+			g_free (plugin_name);
+		}
+	}
+	closedir (d);
+}
+
+void
+plugins_init(void)
+{
+	char *plugin_dir;
+	char *home_dir = getenv ("HOME");
+	
+	if (!g_module_supported())
+		return;
+
+	g_print ("plugins_init()\n");
+
+	/* Load the user plugins */
+	plugin_dir = g_copy_strings (home_dir ? home_dir : "", "/.gnumeric/plugins", NULL);
+	plugin_load_plugins_in_dir (plugin_dir);
+	g_free (plugin_dir);
+
+	/* Load the system plugins */
+	plugin_dir = gnome_unconditional_libdir_file ("gnumeric/plugins");
+	plugin_load_plugins_in_dir (plugin_dir);
+	g_free (plugin_dir);
+}
+

src/plugin.h

+#ifndef _PLUGIN_H
+#define _PLUGIN_H
+
+#include <gmodule.h>
+
+struct PluginData
+{
+	GModule *handle;
+	int     (*init_plugin)    (struct PluginData *);
+	void    (*cleanup_plugin) (struct PluginData *);
+	int     refcount;
+	gchar   *title;
+	
+	/* filled in by plugin */
+	void    *private;
+};
+
+typedef struct PluginData PluginData;
+
+extern GList *plugin_list;
+
+void           plugins_init          (void);
+PluginData    *plugin_load           (gchar *filename);
+void           plugin_unload         (PluginData *pd);
+GtkWidget     *plugin_manager_new    (void);
+
+#endif

src/workbook.c

@@ -13,6 +13,7 @@
 #include "gnumeric-sheet.h"
 #include "dialogs.h"
 #include "xml-io.h"
+#include "plugin.h"
 #include "pixmaps.h"
 
 /* The locations within the main table in the workbook */
@@ -58,6 +59,13 @@ save_as_cmd (GtkWidget *widget, Workbook *wb)
 	workbook_save_as (wb);
 }
 
+static void
+plugins_cmd (GtkWidget *widget, Workbook *wb)
+{
+	GtkWidget *pm = plugin_manager_new();
+	gtk_widget_show(pm);
+}
+
 static void
 set_selection_halign (Workbook *wb, StyleHAlignFlags align)
 {
@@ -275,6 +283,7 @@ static GnomeUIInfo workbook_menu_file [] = {
 	  GNOME_APP_PIXMAP_STOCK, GNOME_STOCK_MENU_SAVE },
 	{ GNOME_APP_UI_ITEM, N_("Save as..."), NULL, save_as_cmd, NULL, NULL,
 	  GNOME_APP_PIXMAP_STOCK, GNOME_STOCK_MENU_SAVE },
+	{ GNOME_APP_UI_ITEM, N_("Plugins..."), NULL, plugins_cmd },
 	{ GNOME_APP_UI_ITEM, N_("Exit"), NULL, quit_cmd, NULL, NULL,
 	  GNOME_APP_PIXMAP_STOCK, GNOME_STOCK_MENU_EXIT },
 	GNOMEUIINFO_END