From 31e16bd8f386dc292e60489d4a17227804bdc2e6 Mon Sep 17 00:00:00 2001 From: Carlos Garcia Campos Date: Fri, 28 Dec 2007 18:13:32 +0000 Subject: Plugin system for backends. Fixes bug #351348. 2007-12-28 Carlos Garcia Campos * configure.ac: * Makefile.am: * po/POTFILES.in: * backend/comics/Makefile.am: * backend/comics/comics-document.[ch]: * backend/comics/comicsdocument.evince-backend.in: * backend/djvu/Makefile.am: * backend/djvu/djvu-document.[ch]: * backend/djvu/djvudocument.evince-backend.in: * backend/dvi/Makefile.am: * backend/dvi/dvi-document.[c]: * backend/dvi/dvidocument.evince-backend.in: * backend/impress/Makefile.am: * backend/impress/impress-document.[ch]: * backend/impress/impressdocument.evince-backend.in: * backend/pdf/Makefile.am: * backend/pdf/ev-poppler.cc: * backend/pdf/ev-poppler.h: * backend/pdf/pdfdocument.evince-backend.in: * backend/pixbuf/Makefile.am: * backend/pixbuf/pixbuf-document.[ch]: * backend/pixbuf/pixbufdocument.evince-backend.in: * backend/ps/Makefile.am: * backend/ps/ev-spectre.[ch]: * backend/ps/ps-document.[ch]: * backend/ps/psdocument.evince-backend.in: * backend/tiff/Makefile.am: * backend/tiff/tiff-document.[ch]: * backend/tiff/tiffdocument.evince-backend.in: * libdocument/Makefile.am: * libdocument/ev-backends-manager.[ch]: * libdocument/ev-module.[ch]: * libdocument/ev-document.h: * libdocument/ev-document-factory.[ch]: (gdk_pixbuf_mime_type_list), (mime_type_supported_by_gdk_pixbuf), (get_compression_from_mime_type), (get_document_from_uri), (ev_document_factory_get_document), (file_filter_add_mime_types), (ev_document_factory_add_filters): * shell/Makefile.am: * shell/ev-window-title.c: (get_filename_from_uri): * shell/main.c: (main): * thumbnailer/Makefile.am: * thumbnailer/evince-thumbnailer.c: (main): Plugin system for backends. Fixes bug #351348. svn path=/trunk/; revision=2786 --- (limited to 'libdocument/ev-backends-manager.c') diff --git a/libdocument/ev-backends-manager.c b/libdocument/ev-backends-manager.c new file mode 100644 index 0000000..0f501a1 --- /dev/null +++ b/libdocument/ev-backends-manager.c @@ -0,0 +1,291 @@ +/* this file is part of evince, a gnome document viewer + * + * Copyright (C) 2007 Carlos Garcia Campos + * + * Evince 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. + * + * Evince 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 + +#include + +#include "ev-module.h" +#include "ev-backends-manager.h" + +static GList *ev_backends_list = NULL; + +typedef struct _EvBackendInfo EvBackendInfo; +struct _EvBackendInfo { + gchar *module_name; + GTypeModule *module; + + GType type_id; + + gchar *type_desc; + gchar **mime_types; +}; + +#define EV_BACKENDS_GROUP "Evince Backend" +#define EV_BACKENDS_EXTENSION ".evince-backend" + +static void +ev_backend_info_free (EvBackendInfo *info) +{ + g_free (info->module_name); + g_free (info->type_desc); + g_strfreev (info->mime_types); + g_free (info); +} + +static EvBackendInfo * +ev_backends_manager_load_backend (const gchar *file) +{ + EvBackendInfo *info; + GKeyFile *backend_file = NULL; + GError *error = NULL; + + backend_file = g_key_file_new (); + if (!g_key_file_load_from_file (backend_file, file, G_KEY_FILE_NONE, &error)) { + g_warning ("Error opening backend file %s: %s", + file, error->message); + g_error_free (error); + g_key_file_free (backend_file); + + return NULL; + } + + info = g_new0 (EvBackendInfo, 1); + info->module_name = g_key_file_get_string (backend_file, EV_BACKENDS_GROUP, + "Module", NULL); + if (!info->module_name) { + g_warning ("Bad evince backend file %s: Could not find 'Module'", + file); + ev_backend_info_free (info); + g_key_file_free (backend_file); + + return NULL; + } + + info->type_desc = g_key_file_get_locale_string (backend_file, EV_BACKENDS_GROUP, + "TypeDescription", NULL, NULL); + if (!info->type_desc) { + g_warning ("Bad evince backend file %s: Could not find 'TypeDescription'", + file); + ev_backend_info_free (info); + g_key_file_free (backend_file); + + return NULL; + } + + info->mime_types = g_key_file_get_string_list (backend_file, EV_BACKENDS_GROUP, + "MimeType", NULL, NULL); + if (!info->mime_types) { + g_warning ("Bad evince backend file %s: Could not find 'MimeType'", + file); + ev_backend_info_free (info); + g_key_file_free (backend_file); + + return NULL; + } + + g_key_file_free (backend_file); + + return info; +} + +static gboolean +ev_backends_manager_load (void) +{ + GDir *dir; + const gchar *dirent; + GError *error = NULL; + + dir = g_dir_open (EV_BACKENDSDIR, 0, &error); + if (!dir) { + g_warning (error->message); + g_error_free (error); + + return FALSE; + } + + while ((dirent = g_dir_read_name (dir))) { + EvBackendInfo *info; + gchar *file; + + if (!g_str_has_suffix (dirent, EV_BACKENDS_EXTENSION)) + continue; + + file = g_build_filename (EV_BACKENDSDIR, dirent, NULL); + info = ev_backends_manager_load_backend (file); + g_free (file); + + if (!info) + continue; + + ev_backends_list = g_list_prepend (ev_backends_list, info); + } + + return TRUE; +} + +gboolean +ev_backends_manager_init (void) +{ + if (ev_backends_list) + return FALSE; + + return ev_backends_manager_load (); +} + +void +ev_backends_manager_shutdown (void) +{ + g_list_foreach (ev_backends_list, (GFunc)ev_backend_info_free, NULL); + g_list_free (ev_backends_list); + ev_backends_list = NULL; +} + +static EvBackendInfo * +ev_backends_manager_get_backend_info (const gchar *mime_type) +{ + GList *l; + + for (l = ev_backends_list; l; l = g_list_next (l)) { + EvBackendInfo *info; + gint i = 0; + const char *mime; + + info = (EvBackendInfo *)l->data; + + while ((mime = info->mime_types[i++])) { + if (g_ascii_strcasecmp (mime, mime_type) == 0) + return info; + } + } + + return NULL; +} + +EvDocument * +ev_backends_manager_get_document (const gchar *mime_type) +{ + EvDocument *document; + EvBackendInfo *info; + + info = ev_backends_manager_get_backend_info (mime_type); + if (!info) + return NULL; + + if (!info->module) { + gchar *path; + + path = g_module_build_path (EV_BACKENDSDIR, info->module_name); + info->module = G_TYPE_MODULE (ev_module_new (path)); + g_free (path); + } + + if (!g_type_module_use (info->module)) { + g_warning ("Cannot load backend '%s' since file '%s' cannot be read.", + info->module_name, + ev_module_get_path (EV_MODULE (info->module))); + g_object_unref (G_OBJECT (info->module)); + info->module = NULL; + + return NULL; + } + + document = EV_DOCUMENT (ev_module_new_object (EV_MODULE (info->module))); + g_type_module_unuse (info->module); + + return document; +} + +static EvBackendInfo * +get_document_backend_info (EvDocument *document) +{ + GList *l; + + for (l = ev_backends_list; l; l = g_list_next (l)) { + EvBackendInfo *info; + GType type_id; + + info = (EvBackendInfo *)l->data; + + if (!info->module) + continue; + + type_id = ev_module_get_object_type (EV_MODULE (info->module)); + + if (G_TYPE_CHECK_INSTANCE_TYPE (document, type_id)) { + return info; + } + } + + return NULL; +} + +const gchar * +ev_backends_manager_get_document_module_name (EvDocument *document) +{ + EvBackendInfo *info; + + info = get_document_backend_info (document); + return info ? info->module_name : NULL; +} + +static EvTypeInfo * +ev_type_info_new (const gchar *desc, const gchar **mime_types) +{ + EvTypeInfo *info; + + info = g_new (EvTypeInfo, 1); + + info->desc = desc; + info->mime_types = mime_types; + + return info; +} + +EvTypeInfo * +ev_backends_manager_get_document_type_info (EvDocument *document) +{ + EvBackendInfo *info; + + info = get_document_backend_info (document); + return info ? + ev_type_info_new (info->type_desc, + (const gchar **)info->mime_types) + : NULL; +} + +GList * +ev_backends_manager_get_all_types_info (void) +{ + GList *l; + GList *retval = NULL; + + for (l = ev_backends_list; l; l = g_list_next (l)) { + EvBackendInfo *info; + EvTypeInfo *type_info; + + info = (EvBackendInfo *)l->data; + + type_info = ev_type_info_new (info->type_desc, + (const gchar **)info->mime_types); + retval = g_list_prepend (retval, type_info); + } + + return retval; +} -- cgit v0.9.1