1 /*****************************************************************************
2 * services_discovery.c : Services discovery using lua scripts
3 *****************************************************************************
4 * Copyright (C) 2010 VideoLAN and AUTHORS
6 * Authors: Fabio Ritrovato <sephiroth87 at videolan dot org>
7 * RĂ©mi Duraffort <ivoire at videolan -dot- org>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
22 *****************************************************************************/
28 #include <vlc_common.h>
29 #include <vlc_services_discovery.h>
34 /*****************************************************************************
36 *****************************************************************************/
37 static void *Run( void * );
38 static int DoSearch( services_discovery_t *p_sd, const char *psz_query );
39 static int FillDescriptor( services_discovery_t *, services_discovery_descriptor_t * );
40 static int Control( services_discovery_t *p_sd, int i_command, va_list args );
42 static const char * const ppsz_sd_options[] = { "sd", "longname", NULL };
44 /*****************************************************************************
46 *****************************************************************************/
47 struct services_discovery_sys_t
60 static const luaL_Reg p_reg[] = { { NULL, NULL } };
62 /*****************************************************************************
63 * Open: initialize and create stuff
64 *****************************************************************************/
65 int Open_LuaSD( vlc_object_t *p_this )
67 services_discovery_t *p_sd = ( services_discovery_t * )p_this;
68 services_discovery_sys_t *p_sys;
72 if( !strcmp( p_sd->psz_name, "lua" ) )
74 // We want to load the module name "lua"
75 // This module can be used to load lua script not registered
76 // as builtin lua SD modules.
77 config_ChainParse( p_sd, "lua-", ppsz_sd_options, p_sd->p_cfg );
78 psz_name = var_GetString( p_sd, "lua-sd" );
82 // We are loading a builtin lua sd module.
83 psz_name = strdup(p_sd->psz_name);
86 if( !( p_sys = malloc( sizeof( services_discovery_sys_t ) ) ) )
92 p_sd->pf_control = Control;
93 p_sys->psz_filename = vlclua_find_file( p_this, "sd", psz_name );
94 if( !p_sys->psz_filename )
96 msg_Err( p_sd, "Couldn't find lua services discovery script \"%s\".",
105 msg_Err( p_sd, "Could not create new Lua State" );
108 vlclua_set_this( L, p_sd );
110 luaL_register( L, "vlc", p_reg );
116 luaopen_strings( L );
117 luaopen_variables( L );
119 luaopen_gettext( L );
123 if( vlclua_add_modules_path( p_sd, L, p_sys->psz_filename ) )
125 msg_Warn( p_sd, "Error while setting the module search path for %s",
126 p_sys->psz_filename );
129 if( luaL_dofile( L, p_sys->psz_filename ) )
131 msg_Err( p_sd, "Error loading script %s: %s", p_sys->psz_filename,
132 lua_tostring( L, lua_gettop( L ) ) );
137 vlc_mutex_init( &p_sys->lock );
138 vlc_cond_init( &p_sys->cond );
139 p_sys->b_exiting = false;
140 TAB_INIT( p_sys->i_query, p_sys->ppsz_query );
142 if( vlc_clone( &p_sys->thread, Run, p_sd, VLC_THREAD_PRIORITY_LOW ) )
144 TAB_CLEAN( p_sys->i_query, p_sys->ppsz_query );
145 vlc_cond_destroy( &p_sys->cond );
146 vlc_mutex_destroy( &p_sys->lock );
154 free( p_sys->psz_filename );
159 /*****************************************************************************
161 *****************************************************************************/
162 void Close_LuaSD( vlc_object_t *p_this )
164 services_discovery_t *p_sd = ( services_discovery_t * )p_this;
165 services_discovery_sys_t *p_sys = p_sd->p_sys;
167 vlc_mutex_lock( &p_sys->lock );
168 p_sys->b_exiting = true;
169 vlc_mutex_unlock( &p_sys->lock );
171 vlc_cancel( p_sys->thread );
172 vlc_join( p_sys->thread, NULL );
174 for( int i = 0; i < p_sys->i_query; i++ )
175 free( p_sys->ppsz_query[i] );
176 TAB_CLEAN( p_sys->i_query, p_sys->ppsz_query );
178 vlc_cond_destroy( &p_sys->cond );
179 vlc_mutex_destroy( &p_sys->lock );
180 free( p_sys->psz_filename );
181 lua_close( p_sys->L );
185 /*****************************************************************************
186 * Run: Thread entry-point
187 ****************************************************************************/
188 static void* Run( void *data )
190 services_discovery_t *p_sd = ( services_discovery_t * )data;
191 services_discovery_sys_t *p_sys = p_sd->p_sys;
192 lua_State *L = p_sys->L;
194 int cancel = vlc_savecancel();
196 lua_getglobal( L, "main" );
197 if( !lua_isfunction( L, lua_gettop( L ) ) || lua_pcall( L, 0, 1, 0 ) )
199 msg_Err( p_sd, "Error while running script %s, "
200 "function main(): %s", p_sys->psz_filename,
201 lua_tostring( L, lua_gettop( L ) ) );
203 vlc_restorecancel( cancel );
206 msg_Dbg( p_sd, "LuaSD script loaded: %s", p_sys->psz_filename );
208 /* Force garbage collection, because the core will keep the SD
209 * open, but lua will never gc until lua_close(). */
210 lua_gc( L, LUA_GCCOLLECT, 0 );
212 vlc_restorecancel( cancel );
214 /* Main loop to handle search requests */
215 vlc_mutex_lock( &p_sys->lock );
216 mutex_cleanup_push( &p_sys->lock );
217 while( !p_sys->b_exiting )
219 /* Wait for a request */
220 while( !p_sys->i_query )
221 vlc_cond_wait( &p_sys->cond, &p_sys->lock );
223 /* Execute every query each one protected against cancelation */
224 cancel = vlc_savecancel();
225 while( !p_sys->b_exiting && p_sys->i_query )
227 char *psz_query = p_sys->ppsz_query[p_sys->i_query - 1];
228 REMOVE_ELEM( p_sys->ppsz_query, p_sys->i_query, p_sys->i_query - 1 );
230 vlc_mutex_unlock( &p_sys->lock );
231 DoSearch( p_sd, psz_query );
233 vlc_mutex_lock( &p_sys->lock );
235 /* Force garbage collection, because the core will keep the SD
236 * open, but lua will never gc until lua_close(). */
237 lua_gc( L, LUA_GCCOLLECT, 0 );
239 vlc_restorecancel( cancel );
246 /*****************************************************************************
247 * Control: services discrovery control
248 ****************************************************************************/
249 static int Control( services_discovery_t *p_sd, int i_command, va_list args )
251 services_discovery_sys_t *p_sys = p_sd->p_sys;
257 const char *psz_query = va_arg( args, const char * );
258 vlc_mutex_lock( &p_sys->lock );
259 TAB_APPEND( p_sys->i_query, p_sys->ppsz_query, strdup( psz_query ) );
260 vlc_cond_signal( &p_sys->cond );
261 vlc_mutex_unlock( &p_sys->lock );
265 case SD_CMD_DESCRIPTOR:
267 services_discovery_descriptor_t *p_desc = va_arg( args,
268 services_discovery_descriptor_t * );
269 return FillDescriptor( p_sd, p_desc );
276 /*****************************************************************************
277 * DoSearch: search for a given query
278 ****************************************************************************/
279 static int DoSearch( services_discovery_t *p_sd, const char *psz_query )
281 services_discovery_sys_t *p_sys = p_sd->p_sys;
282 lua_State *L = p_sys->L;
284 /* Lookup for the 'search' function */
285 lua_getglobal( L, "search" );
286 if( !lua_isfunction( L, lua_gettop( L ) ) )
288 msg_Err( p_sd, "The script '%s' does not define any 'search' function",
289 p_sys->psz_filename );
295 lua_pushstring( L, psz_query );
297 /* Call the 'search' function */
298 if( lua_pcall( L, 1, 0, 0 ) )
300 msg_Err( p_sd, "Error while running the script '%s': %s",
301 p_sys->psz_filename, lua_tostring( L, lua_gettop( L ) ) );
309 /** List of capabilities */
310 static const char *const ppsz_capabilities[] = {
315 /*****************************************************************************
316 * FillDescriptor: call the descriptor function and fill the structure
317 ****************************************************************************/
318 static int FillDescriptor( services_discovery_t *p_sd,
319 services_discovery_descriptor_t *p_desc )
321 services_discovery_sys_t *p_sys = p_sd->p_sys;
322 int i_ret = VLC_EGENERIC;
324 /* Create a new lua thread */
325 lua_State *L = luaL_newstate();
326 if( luaL_dofile( L, p_sys->psz_filename ) )
328 msg_Err( p_sd, "Error loading script %s: %s", p_sys->psz_filename,
329 lua_tostring( L, -1 ) );
333 /* Call the "descriptor" function */
334 lua_getglobal( L, "descriptor" );
335 if( !lua_isfunction( L, -1 ) || lua_pcall( L, 0, 1, 0 ) )
337 msg_Warn( p_sd, "Error getting the descriptor in '%s': %s",
338 p_sys->psz_filename, lua_tostring( L, -1 ) );
342 /* Get the different fields of the returned table */
343 lua_getfield( L, -1, "short_description" );
344 p_desc->psz_short_desc = luaL_strdupornull( L, -1 );
347 lua_getfield( L, -1, "icon" );
348 p_desc->psz_icon_url = luaL_strdupornull( L, -1 );
351 lua_getfield( L, -1, "url" );
352 p_desc->psz_url = luaL_strdupornull( L, -1 );
355 lua_getfield( L, -1, "capabilities" );
356 p_desc->i_capabilities = 0;
357 if( lua_istable( L, -1 ) )
359 /* List all table entries */
361 while( lua_next( L, -2 ) != 0 )
363 /* Key is at index -2 and value at index -1 */
364 const char *psz_cap = luaL_checkstring( L, -1 );
366 const char *psz_iter;
367 for( psz_iter = *ppsz_capabilities; psz_iter;
368 psz_iter = ppsz_capabilities[ ++i_cap ] )
370 if( !strcmp( psz_iter, psz_cap ) )
372 p_desc->i_capabilities |= 1 << i_cap;
377 msg_Warn( p_sd, "Services discovery capability '%s' unknown in "
378 "script '%s'", psz_cap, p_sys->psz_filename );