Change GTK UI builder handling to use resource API

GTK UI builder resources have till now been exclusively stored on disc
requiring netsurf to ship numerous additional resource files. This
requires going to disc every time a UI action is performed which can
become a lot of unwanted file handling.

GLib/GTK has moved towards GResource handling for such resources
instead. It now seems that migrating to this style of usage is
expected and indeed the only portable way to include pixbufs.

This introduces an API to hide the various implementation details of
how resources are handled from the rest of the codebase.

1 files changed, 285 insertions, 1 deletions

diff --git a/gtk/resources.c b/gtk/resources.c
index e6ad951b8..d4e8b2056 100644
--- a/gtk/resources.c
+++ b/gtk/resources.c
@@ -20,11 +20,20 @@
  * \file
  * Implementation of gtk builtin resource handling.
  *
- * \todo resource handling in gtk3 has switched to using GResource
+ * This presents a unified interface to the rest of the codebase to
+ * obtain resources. Note this is not anything to do with the resource
+ * scheme handling beyond possibly providing the underlying data.
+ *
  */
 
+#include <stdlib.h>
+#include <string.h>
 #include <gtk/gtk.h>
 
+#include "utils/log.h"
+#include "utils/filepath.h"
+
+#include "gtk/compat.h"
 #include "gtk/resources.h"
 
 #ifdef __GNUC__
@@ -33,6 +42,41 @@ extern const guint8 menu_cursor_pixdata[] __attribute__ ((__aligned__ (4)));
 extern const guint8 menu_cursor_pixdata[];
 #endif
 
+enum nsgtk_resource_type_e {
+	NSGTK_RESOURCE_FILE,
+	NSGTK_RESOURCE_BUILTIN,
+};
+
+struct nsgtk_resource_s {
+	const char *name;
+	unsigned int len;
+	enum nsgtk_resource_type_e type;
+	char *path;
+};
+
+static struct nsgtk_resource_s ui_resource[] = {
+	{ "netsurf", 7, NSGTK_RESOURCE_FILE, NULL },
+	{ "tabcontents", 10, NSGTK_RESOURCE_FILE, NULL },
+	{ "password", 8, NSGTK_RESOURCE_FILE, NULL },
+	{ "login", 5, NSGTK_RESOURCE_FILE, NULL },
+	{ "ssl", 3, NSGTK_RESOURCE_FILE, NULL },
+	{ "toolbar", 7, NSGTK_RESOURCE_FILE, NULL },
+	{ "downloads", 9, NSGTK_RESOURCE_FILE, NULL },
+	{ "history", 7, NSGTK_RESOURCE_FILE, NULL },
+	{ "options", 7, NSGTK_RESOURCE_FILE, NULL },
+	{ "hotlist", 7, NSGTK_RESOURCE_FILE, NULL },
+	{ "cookies", 7, NSGTK_RESOURCE_FILE, NULL },
+	{ "viewdata", 8, NSGTK_RESOURCE_FILE, NULL },
+	{ "warning", 7, NSGTK_RESOURCE_FILE, NULL },
+	{ NULL, 0, NSGTK_RESOURCE_FILE, NULL },
+};
+
+static struct nsgtk_resource_s gen_resource[] = {
+	{ "favicon.png", 11, NSGTK_RESOURCE_FILE, NULL },
+	{ NULL, 0, NSGTK_RESOURCE_FILE, NULL },
+};
+
+/* exported interface documented in gtk/resources.h */
 GdkCursor *nsgtk_create_menu_cursor(void)
 {
 	GdkCursor *cursor = NULL;
@@ -44,3 +88,243 @@ GdkCursor *nsgtk_create_menu_cursor(void)
 
 	return cursor;
 }
+
+
+/*
+ * locate a resource
+ *
+ * The way GTK accesses resource files has changed greatly between
+ * releases. This initilises the interface that hides all the
+ * implementation details from the rest of the code.
+ *
+ * If the GResource is not enabled or the item cannot be found in the
+ * compiled in resources the files will be loaded directly from disc
+ * instead.
+ *
+ * \param respath A string vector containing the valid resource search paths
+ * \param ui_res A resource entry to initialise
+ */
+static nserror
+init_resource(char **respath, struct nsgtk_resource_s *resource)
+{
+	int resnamelen;
+	char *resname;
+
+#ifdef WITH_GRESOURCE
+	gboolean present;
+
+	resnamelen = snprintf(NULL, 0, "/org/netsurf/%s", resource->name);
+
+	resname = malloc(resnamelen + 1);
+	if (resname == NULL) {
+		return NSERROR_NOMEM;
+	}
+	snprintf(resname, resnamelen + 1, "/org/netsurf/%s", resource->name);
+
+	present = g_resources_get_info(resname,
+				       G_RESOURCE_LOOKUP_FLAGS_NONE,
+				       NULL, NULL, NULL);
+	if (present == TRUE) {
+		/* found an entry in the resources */
+		resource->path = resname;
+		resource->type = NSGTK_RESOURCE_BUILTIN;
+		LOG("Found gresource path %s", resource->path);
+		return NSERROR_OK;
+	}
+	LOG("gresource \"%s\" not found", resname);
+	free(resname);
+#endif
+
+	resname = filepath_find(respath, resource->name);
+	if (resname == NULL) {
+		LOG("Unable to find resource %s on resource path",
+		    resource->name);
+		return NSERROR_NOT_FOUND;
+	}
+
+	/* found an entry on the path */
+	resource->path = resname;
+	resource->type = NSGTK_RESOURCE_FILE;
+
+	LOG("Found file resource path %s", resource->path);
+	return NSERROR_OK;
+}
+
+/*
+ * locate a ui resource
+ *
+ * UI resources need their resource name changing to account for gtk versions
+ *
+ * \param respath A string vector containing the valid resource search paths
+ * \param ui_res A resource entry to initialise
+ */
+static nserror init_ui_resource(char **respath, struct nsgtk_resource_s *ui_res)
+{
+#if GTK_CHECK_VERSION(3,0,0)
+	int gtkv = 3;
+#else
+	int gtkv = 2;
+#endif
+	int resnamelen;
+	char *resname;
+	struct nsgtk_resource_s resource;
+	nserror res;
+
+	resnamelen = ui_res->len + 10; /* allow for the expanded ui name */
+
+	resname = malloc(resnamelen);
+	if (resname == NULL) {
+		return NSERROR_NOMEM;
+	}
+	snprintf(resname, resnamelen, "%s.gtk%d.ui", ui_res->name, gtkv);
+	resource.name = resname;
+	resource.len = ui_res->len;
+	resource.path = NULL;
+
+	res = init_resource(respath, &resource);
+
+	ui_res->path = resource.path;
+	ui_res->type = resource.type;
+
+	free(resname);
+
+	return res;
+}
+
+#define SHOW_GRESOURCE
+
+/**
+ * Initialise UI resource table
+ *
+ */
+nserror nsgtk_init_resources(char **respath)
+{
+	struct nsgtk_resource_s *resource;
+	nserror res;
+
+#ifdef SHOW_GRESOURCE
+	const char *nspath = "/org/netsurf";
+	char **reslist;
+	char **cur;
+	GError* gerror = NULL;
+	reslist = g_resources_enumerate_children(nspath,G_RESOURCE_LOOKUP_FLAGS_NONE, &gerror);
+	if (gerror) {
+		LOG("gerror %s", gerror->message);
+		g_error_free(gerror);
+
+	} else {
+	cur = reslist;
+	while (cur != NULL && *cur != NULL) {
+		LOG("gres %s", *cur);
+		cur++;
+	}
+	g_strfreev(reslist);
+	}
+#endif
+
+	/* walk the ui resource table and initialise all its members */
+	resource = &ui_resource[0];
+	while (resource->name != NULL) {
+		res = init_ui_resource(respath, resource);
+		if (res != NSERROR_OK) {
+			return res;
+		}
+		resource++;
+	}
+
+	/* walk the general resource table and initialise all its members */
+	resource = &gen_resource[0];
+	while (resource->name != NULL) {
+		res = init_resource(respath, resource);
+		if (res != NSERROR_OK) {
+			return res;
+		}
+		resource++;
+	}
+
+
+	return NSERROR_OK;
+}
+
+static struct nsgtk_resource_s *
+find_resource_from_name(const char *resname, struct nsgtk_resource_s *resource)
+{
+	/* find resource from name */
+	while ((resource->name != NULL) &&
+	       ((resname[0] != resource->name[0]) ||
+		(strncmp(resource->name, resname, resource->len) != 0))) {
+		resource++;
+	}
+	return resource;
+}
+
+/* exported interface documented in gtk/resources.h */
+nserror
+nsgdk_pixbuf_new_from_resname(const char *resname, GdkPixbuf **pixbuf_out)
+{
+	struct nsgtk_resource_s *resource;
+	GdkPixbuf *new_pixbuf;
+	GError* error = NULL;
+
+	resource = find_resource_from_name(resname, &gen_resource[0]);
+	if (resource->name == NULL) {
+		return NSERROR_NOT_FOUND;
+	}
+
+	if (resource->type == NSGTK_RESOURCE_FILE) {
+		new_pixbuf = gdk_pixbuf_new_from_file(resource->path, &error);
+	} else {
+		new_pixbuf = gdk_pixbuf_new_from_resource(resource->path, &error);
+	}
+	if (new_pixbuf == NULL) {
+		LOG("Unable to create pixbuf from file for %s with path %s \"%s\"",
+			    resource->name, resource->path, error->message);
+		g_error_free(error);
+		return NSERROR_INIT_FAILED;
+	}
+	*pixbuf_out = new_pixbuf;
+
+	return NSERROR_OK;
+}
+
+/* exported interface documented in gtk/resources.h */
+nserror
+nsgtk_builder_new_from_resname(const char *resname, GtkBuilder **builder_out)
+{
+	GtkBuilder *new_builder;
+	struct nsgtk_resource_s *ui_res;
+	GError* error = NULL;
+
+	ui_res = find_resource_from_name(resname, &ui_resource[0]);
+	if (ui_res->name == NULL) {
+		return NSERROR_NOT_FOUND;
+	}
+
+	new_builder = gtk_builder_new();
+
+	if (ui_res->type == NSGTK_RESOURCE_FILE) {
+		if (!gtk_builder_add_from_file(new_builder,
+					       ui_res->path,
+					       &error)) {
+			LOG("Unable to add UI builder from file for %s with path %s \"%s\"",
+			    ui_res->name, ui_res->path, error->message);
+			g_error_free(error);
+			g_object_unref(G_OBJECT(new_builder));
+			return NSERROR_INIT_FAILED;
+		}
+	} else {
+		if (!nsgtk_builder_add_from_resource(new_builder,
+						     ui_res->path,
+						     &error)) {
+			LOG("Unable to add UI builder from resource for %s with path %s \"%s\"",
+			    ui_res->name, ui_res->path, error->message);
+			g_error_free(error);
+			g_object_unref(G_OBJECT(new_builder));
+			return NSERROR_INIT_FAILED;
+		}
+	}
+
+	*builder_out = new_builder;
+
+	return NSERROR_OK;
+}