demoproxy: add a demo proxy showcasing how to create a proxy plugin

This demo proxy does not actually do anything useful. It simply loads
pseudo-plugins from an ini-style file. The point is that there will be a plugin
in the PM dialog for each ini. Each ini-plugin also causes a menu item to be
generated.

plugins/Makefile.am

 # Adapted from Pidgin's plugins/Makefile.am, thanks
 
 EXTRA_DIST = \
-	makefile.win32
+	makefile.win32 \
+	demoproxytest.px
 
 plugindir = $(libdir)/geany
 
@@ -11,6 +12,7 @@ plugins_include_HEADERS = \
 	geanyplugin.h
 
 demoplugin_la_LDFLAGS    = -module -avoid-version -no-undefined
+demoproxy_la_LDFLAGS     = -module -avoid-version -no-undefined
 classbuilder_la_LDFLAGS  = -module -avoid-version -no-undefined
 htmlchars_la_LDFLAGS     = -module -avoid-version -no-undefined
 export_la_LDFLAGS        = -module -avoid-version -no-undefined
@@ -30,9 +32,11 @@ plugin_LTLIBRARIES = \
 
 # Plugins not to be installed
 noinst_LTLIBRARIES = \
-	demoplugin.la
+	demoplugin.la  \
+	demoproxy.la
 
 demoplugin_la_SOURCES    = demoplugin.c
+demoproxy_la_SOURCES     = demoproxy.c
 classbuilder_la_SOURCES  = classbuilder.c
 htmlchars_la_SOURCES     = htmlchars.c
 export_la_SOURCES        = export.c
@@ -41,6 +45,7 @@ filebrowser_la_SOURCES   = filebrowser.c
 splitwindow_la_SOURCES   = splitwindow.c
 
 demoplugin_la_CFLAGS    = -DG_LOG_DOMAIN=\""Demoplugin"\" -DLOCALEDIR=\""$(LOCALEDIR)"\"
+demoproxy_la_CFLAGS     = -DG_LOG_DOMAIN=\""Demoproxy"\"
 classbuilder_la_CFLAGS  = -DG_LOG_DOMAIN=\""Classbuilder"\"
 htmlchars_la_CFLAGS     = -DG_LOG_DOMAIN=\""HTMLChars"\"
 export_la_CFLAGS        = -DG_LOG_DOMAIN=\""Export"\"
@@ -49,6 +54,7 @@ filebrowser_la_CFLAGS   = -DG_LOG_DOMAIN=\""FileBrowser"\"
 splitwindow_la_CFLAGS   = -DG_LOG_DOMAIN=\""SplitWindow"\"
 
 demoplugin_la_LIBADD    = $(top_builddir)/src/libgeany.la $(GTK_LIBS)
+demoproxy_la_LIBADD     = $(top_builddir)/src/libgeany.la $(GTK_LIBS)
 classbuilder_la_LIBADD  = $(top_builddir)/src/libgeany.la $(GTK_LIBS)
 htmlchars_la_LIBADD     = $(top_builddir)/src/libgeany.la $(GTK_LIBS)
 export_la_LIBADD        = $(top_builddir)/src/libgeany.la $(GTK_LIBS) -lm

plugins/demoproxy.c

+/*
+ *      demoproxy.c - this file is part of Geany, a fast and lightweight IDE
+ *
+ *      Copyright 2015 Thomas Martitz <kugel(at)rockbox(dot)org>
+ *
+ *      This program is free software; you can redistribute it and/or modify
+ *      it under the terms of the GNU General Public License as published by
+ *      the Free Software Foundation; either version 2 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.,
+ *      51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+/**
+ * Demo proxy - example of a basic proxy plugin for Geany. Sub-plugins add menu items to the
+ * Tools menu and have a help dialog.
+ *
+ * Note: This is compiled but not installed by default. On Unix, you can install it by compiling
+ * Geany and then copying (or symlinking) to the plugins/demoproxy.so and
+ * plugins/demoproxytest.px files to ~/.config/geany/plugins
+ * - it will be loaded at next startup.
+ */
+
+/* plugin API, always comes first */
+#include "geanyplugin.h"
+
+typedef struct {
+	GKeyFile       *file;
+	gchar          *help_text;
+	GSList         *menu_items;
+}
+PluginContext;
+
+
+static gboolean proxy_init(GeanyPlugin *plugin, gpointer pdata)
+{
+	PluginContext *data;
+	gint i = 0;
+	gchar *text;
+
+	data = (PluginContext *) pdata;
+
+	/* Normally, you would instruct the VM/interpreter to call into the actual plugin. The
+	 * plugin would be identified by pdata. Because there is no interpreter for
+	 * .ini files we do it inline, as this is just a demo */
+	data->help_text = g_key_file_get_locale_string(data->file, "Help", "text", NULL, NULL);
+	while (TRUE)
+	{
+		GtkWidget *item;
+		gchar *key = g_strdup_printf("item%d", i++);
+		text = g_key_file_get_locale_string(data->file, "Init", key, NULL, NULL);
+		g_free(key);
+
+		if (!text)
+			break;
+
+		item = gtk_menu_item_new_with_label(text);
+		gtk_widget_show(item);
+		gtk_container_add(GTK_CONTAINER(plugin->geany_data->main_widgets->tools_menu), item);
+		gtk_widget_set_sensitive(item, FALSE);
+		data->menu_items = g_slist_prepend(data->menu_items, (gpointer) item);
+		g_free(text);
+	}
+
+	return TRUE;
+}
+
+
+static void proxy_help(GeanyPlugin *plugin, gpointer pdata)
+{
+	PluginContext *data;
+	GtkWidget *dialog;
+
+	data = (PluginContext *) pdata;
+
+	dialog = gtk_message_dialog_new(
+		GTK_WINDOW(plugin->geany_data->main_widgets->window),
+		GTK_DIALOG_DESTROY_WITH_PARENT,
+		GTK_MESSAGE_INFO,
+		GTK_BUTTONS_OK,
+		"%s", data->help_text);
+	gtk_message_dialog_format_secondary_text(GTK_MESSAGE_DIALOG(dialog),
+		_("(From the %s plugin)"), plugin->info->name);
+
+	gtk_dialog_run(GTK_DIALOG(dialog));
+	gtk_widget_destroy(dialog);
+}
+
+
+static void proxy_cleanup(GeanyPlugin *plugin, gpointer pdata)
+{
+	PluginContext *data = (PluginContext *) pdata;
+
+	g_slist_free_full(data->menu_items, (GDestroyNotify) gtk_widget_destroy);
+	g_free(data->help_text);
+}
+
+
+static gint demoproxy_probe(GeanyPlugin *proxy, const gchar *filename, gpointer pdata)
+{
+	/* We know the extension is right (Geany checks that). For demo purposes we perform an
+	 * additional check. This is not necessary when the extension is unique enough. */
+	gboolean match = FALSE;
+	gchar linebuf[128];
+	FILE *f = fopen(filename, "r");
+	if (f != NULL)
+	{
+		if (fgets(linebuf, sizeof(linebuf), f) != NULL)
+			match = utils_str_equal(linebuf, "#!!PROXY_MAGIC!!\n");
+		fclose(f);
+	}
+	return match ? PROXY_MATCHED : PROXY_IGNORED;
+}
+
+
+static gpointer demoproxy_load(GeanyPlugin *proxy, GeanyPlugin *plugin,
+                               const gchar *filename, gpointer pdata)
+{
+	GKeyFile *file;
+	gboolean result;
+
+	file = g_key_file_new();
+	result = g_key_file_load_from_file(file, filename, 0, NULL);
+
+	if (result)
+	{
+		PluginContext *data = g_new0(PluginContext, 1);
+		data->file = file;
+
+		plugin->info->name = g_key_file_get_locale_string(data->file, "Info", "name", NULL, NULL);
+		plugin->info->description = g_key_file_get_locale_string(data->file, "Info", "description", NULL, NULL);
+		plugin->info->version = g_key_file_get_locale_string(data->file, "Info", "version", NULL, NULL);
+		plugin->info->author = g_key_file_get_locale_string(data->file, "Info", "author", NULL, NULL);
+
+		plugin->funcs->init = proxy_init;
+		plugin->funcs->help = proxy_help;
+		plugin->funcs->cleanup = proxy_cleanup;
+
+		/* Cannot pass g_free as free_func be Geany calls it before unloading, and since 
+		 * demoproxy_unload() accesses the data this would be catastrophic */
+		GEANY_PLUGIN_REGISTER_FULL(plugin, 225, data, NULL);
+		return data;
+	}
+
+	g_key_file_free(file);
+	return NULL;
+}
+
+
+static void demoproxy_unload(GeanyPlugin *proxy, GeanyPlugin *plugin, gpointer load_data, gpointer pdata)
+{
+	PluginContext *data = load_data;
+
+	g_free((gchar *)plugin->info->name);
+	g_free((gchar *)plugin->info->description);
+	g_free((gchar *)plugin->info->version);
+	g_free((gchar *)plugin->info->author);
+
+	g_key_file_free(data->file);
+	g_free(data);
+}
+
+
+/* Called by Geany to initialize the plugin. */
+static gboolean demoproxy_init(GeanyPlugin *plugin, gpointer pdata)
+{
+	const gchar *extensions[] = { "ini", "px", NULL };
+
+	plugin->proxy_funcs->probe  = demoproxy_probe;
+	plugin->proxy_funcs->load   = demoproxy_load;
+	plugin->proxy_funcs->unload = demoproxy_unload;
+
+	return geany_plugin_register_proxy(plugin, extensions);
+}
+
+
+/* Called by Geany before unloading the plugin. */
+static void demoproxy_cleanup(GeanyPlugin *plugin, gpointer data)
+{
+}
+
+
+G_MODULE_EXPORT
+void geany_load_module(GeanyPlugin *plugin)
+{
+	plugin->info->name = _("Demo Proxy");
+	plugin->info->description = _("Example Proxy.");
+	plugin->info->version = "0.1";
+	plugin->info->author = _("The Geany developer team");
+
+	plugin->funcs->init = demoproxy_init;
+	plugin->funcs->cleanup = demoproxy_cleanup;
+
+	GEANY_PLUGIN_REGISTER(plugin, 225);
+}

plugins/demoproxytest.px

+#!!PLUXY_MAGIC!!
+
+[Init]
+item0 = Bam
+item1 = Foo
+item2 = Bar
+
+[Help]
+text = I'm a simple test. Nothing to see!
+
+[Info]
+name = Demo Pluxy Tester
+description = I'm a simple test. Nothing to see!
+version = 0.1
+author = The Geany developer team

po/POTFILES.skip

@@ -6,5 +6,6 @@ geany.desktop.in
 geany.glade
 # no need to translate these files
 plugins/demoplugin.c
+plugins/demoproxy.c
 doc/stash-example.c
 doc/stash-gui-example.c