nkeynes@1024: /**
nkeynes@1024:  * $Id$
nkeynes@1024:  *
nkeynes@1024:  * Plugin loader code
nkeynes@1024:  *
nkeynes@1024:  * Copyright (c) 2009 Nathan Keynes.
nkeynes@1024:  *
nkeynes@1024:  * This program is free software; you can redistribute it and/or modify
nkeynes@1024:  * it under the terms of the GNU General Public License as published by
nkeynes@1024:  * the Free Software Foundation; either version 2 of the License, or
nkeynes@1024:  * (at your option) any later version.
nkeynes@1024:  *
nkeynes@1024:  * This program is distributed in the hope that it will be useful,
nkeynes@1024:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
nkeynes@1024:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
nkeynes@1024:  * GNU General Public License for more details.
nkeynes@1024:  */
nkeynes@1024: 
nkeynes@1027: #include <sys/stat.h>
nkeynes@1024: #include <dirent.h>
nkeynes@1024: #include <dlfcn.h>
nkeynes@1024: #include <string.h>
nkeynes@1024: #include <glib/gmem.h>
nkeynes@1024: #include <glib/gstrfuncs.h>
nkeynes@1024: #include "plugin.h"
nkeynes@1041: #include "lxpaths.h"
nkeynes@1024: 
nkeynes@1024: #ifdef APPLE_BUILD
nkeynes@1024: #define SOEXT ".dylib"
nkeynes@1024: #else
nkeynes@1024: #define SOEXT ".so"
nkeynes@1024: #endif
nkeynes@1024: 
nkeynes@1027: /** Dummy plugin used as a plugin directory marker */
nkeynes@1027: #define DUMMY_PLUGIN ("lxdream_dummy" SOEXT) 
nkeynes@1024: 
nkeynes@1027: const char *plugin_type_string[] = { "undefined", "audio driver", "input driver" };
nkeynes@1027: 
nkeynes@1027: int main(int argc, char *argv[]);
nkeynes@1027: static const char *exec_path = NULL;
nkeynes@1027: 
nkeynes@1027: /**
nkeynes@1027:  * Return the full path to the main binary
nkeynes@1027:  */
nkeynes@1027: static const char *get_exec_path()
nkeynes@1027: {
nkeynes@1027:     if( exec_path == NULL ) {
nkeynes@1027:         Dl_info dli;
nkeynes@1027: 
nkeynes@1027:         /* Use dladdr for this, since it should be available for any platform
nkeynes@1027:          * that we can support plugins on at all.
nkeynes@1027:          */
nkeynes@1027:         if( dladdr( main, &dli) ) {
nkeynes@1027:             gchar *path = g_strdup( dli.dli_fname );
nkeynes@1027:             char *i = strrchr( path, '/' );
nkeynes@1027:             if( i > path ) {
nkeynes@1027:                 *i = '\0';
nkeynes@1027:                 exec_path = path;
nkeynes@1027:             } else {
nkeynes@1027:                 g_free(path);
nkeynes@1027:             }
nkeynes@1027:         }
nkeynes@1027:     }
nkeynes@1027:     return exec_path;
nkeynes@1027: }
nkeynes@1027:     
nkeynes@1027: static gboolean plugin_load( const gchar *plugin_path )
nkeynes@1024: {
nkeynes@1024:     void *so = dlopen(plugin_path, RTLD_NOW|RTLD_LOCAL);
nkeynes@1024:     if( so == NULL ) {
nkeynes@1024:         WARN("Failed to load plugin '%s': %s", plugin_path, dlerror());
nkeynes@1024:         return FALSE;
nkeynes@1024:     }
nkeynes@1024:     
nkeynes@1024:     struct plugin_struct *plugin = (struct plugin_struct *)dlsym(so,"lxdream_plugin_entry");
nkeynes@1024:     if( plugin == NULL ) {
nkeynes@1024:         WARN("Failed to load plugin: '%s': Not an lxdream plugin", plugin_path);
nkeynes@1024:         dlclose(so);
nkeynes@1024:         return FALSE;
nkeynes@1024:     }
nkeynes@1024: 
nkeynes@1024:     if( strcmp(lxdream_short_version, plugin->version) != 0 ) {
nkeynes@1024:         WARN("Failed to load plugin: '%s': Incompatible version (%s)", plugin_path, plugin->version);
nkeynes@1024:         dlclose(so);
nkeynes@1024:         return FALSE;
nkeynes@1024:     }
nkeynes@1024: 
nkeynes@1027:     if( plugin->type == PLUGIN_NONE ) {
nkeynes@1027:         /* 'dummy' plugin - we don't actually want to load it */
nkeynes@1027:         dlclose(so);
nkeynes@1027:         return FALSE;
nkeynes@1027:     }
nkeynes@1027:     
nkeynes@1024:     if( plugin->type < PLUGIN_MIN_TYPE || plugin->type > PLUGIN_MAX_TYPE ) {
nkeynes@1024:         WARN("Failed to load plugin: '%s': Unrecognized plugin type (%d)", plugin_path, plugin->type );
nkeynes@1024:         dlclose(so);
nkeynes@1024:         return FALSE;
nkeynes@1024:     }
nkeynes@1024: 
nkeynes@1024:     if( plugin->register_plugin() == FALSE ) {
nkeynes@1024:         WARN("Failed to load plugin: '%s': Initialization failed", plugin_path);
nkeynes@1024:         dlclose(so);
nkeynes@1024:         return FALSE;
nkeynes@1024:     }
nkeynes@1075:     DEBUG("Loaded %s '%s'", plugin_type_string[plugin->type], plugin->name);
nkeynes@1024:     return TRUE;
nkeynes@1024: }
nkeynes@1024: 
nkeynes@1027: static gboolean has_plugins( const gchar *path )
nkeynes@1027: {
nkeynes@1027:     struct stat st;
nkeynes@1027:     
nkeynes@1027:     gchar *dummy_name = g_strdup_printf( "%s/%s", path, DUMMY_PLUGIN );
nkeynes@1027:     if( stat( dummy_name, &st ) == 0 ) {
nkeynes@1027:         return TRUE;
nkeynes@1027:     } else {
nkeynes@1027:         return FALSE;
nkeynes@1027:     }
nkeynes@1027: }
nkeynes@1027: 
nkeynes@1024: /**
nkeynes@1024:  * Scan the plugin dir and load all valid plugins.
nkeynes@1024:  */
nkeynes@1027: static int plugin_load_all( const gchar *plugin_dir )
nkeynes@1024: {
nkeynes@1071:     int plugin_count = 0;
nkeynes@1024:     struct dirent *ent;
nkeynes@1027:     
nkeynes@1024:     DIR *dir = opendir(plugin_dir);
nkeynes@1024:     if( dir == NULL ) {
nkeynes@1024:         WARN( "Unable to open plugin directory '%s'", plugin_dir );
nkeynes@1024:         return 0;
nkeynes@1024:     }
nkeynes@1024:     
nkeynes@1024:     while( (ent = readdir(dir)) != NULL ) {
nkeynes@1024:         const char *ext = strrchr(ent->d_name, '.');
nkeynes@1024:         if( ext != NULL && strcasecmp(SOEXT,ext) == 0 ) {
nkeynes@1024:             char *libname = g_strdup_printf( "%s/%s", plugin_dir,ent->d_name );
nkeynes@1024:             if( plugin_load( libname ) ) {
nkeynes@1024:                 plugin_count++;
nkeynes@1024:             }
nkeynes@1024:             g_free(libname);
nkeynes@1024:         }
nkeynes@1024:     }
nkeynes@1024:     return plugin_count;
nkeynes@1024: }
nkeynes@1027: 
nkeynes@1027: int plugin_init()
nkeynes@1027: {
nkeynes@1027:     const char *path = get_exec_path();
nkeynes@1027:     if( path == NULL || !has_plugins(path) ) {
nkeynes@1027:         path = get_plugin_path();
nkeynes@1027:     }
nkeynes@1027:     
nkeynes@1075:     DEBUG( "Plugin directory: %s", path );
nkeynes@1027:     return plugin_load_all( path );
nkeynes@1027: }