[vlc-commits] lua/sd: use queue

[Rémi Denis-Courmont]

vlc | branch: master | Rémi Denis-Courmont <remi at remlab.net> | Sat Apr 11 23:45:54 2020 +0300| [65b83f162abd5ea981ace52fe1bcb34f16902db8] | committer: Rémi Denis-Courmont

lua/sd: use queue

This adds missing memory allocation error handling and removes one use of
CV cancellation.

> http://git.videolan.org/gitweb.cgi/vlc.git/?a=commit;h=65b83f162abd5ea981ace52fe1bcb34f16902db8
---

 modules/lua/services_discovery.c | 76 +++++++++++++++-------------------------
 1 file changed, 29 insertions(+), 47 deletions(-)

diff --git a/modules/lua/services_discovery.c b/modules/lua/services_discovery.c
index 3984bf3de8..2dc3621c3b 100644
--- a/modules/lua/services_discovery.c
+++ b/modules/lua/services_discovery.c
@@ -28,6 +28,7 @@
 #include <assert.h>
 #include <vlc_common.h>
 #include <vlc_services_discovery.h>
+#include <vlc_queue.h>
 
 #include "vlc.h"
 #include "libs.h"
@@ -141,14 +142,17 @@ typedef struct
     char *psz_filename;
 
     vlc_thread_t thread;
-    vlc_mutex_t lock;
-    vlc_cond_t cond;
-
-    char **ppsz_query;
-    int i_query;
+    vlc_queue_t queue;
+    bool dead;
 } services_discovery_sys_t;
 static const luaL_Reg p_reg[] = { { NULL, NULL } };
 
+struct sd_query
+{
+    struct sd_query *next;
+    char query[];
+};
+
 /*****************************************************************************
  * Open: initialize and create stuff
  *****************************************************************************/
@@ -232,13 +236,11 @@ int Open_LuaSD( vlc_object_t *p_this )
         p_sd->description = p_sd->psz_name;
 
     p_sys->L = L;
-    vlc_mutex_init( &p_sys->lock );
-    vlc_cond_init( &p_sys->cond );
-    TAB_INIT( p_sys->i_query, p_sys->ppsz_query );
+    p_sys->dead = false;
+    vlc_queue_Init( &p_sys->queue, offsetof (struct sd_query, next) );
 
     if( vlc_clone( &p_sys->thread, Run, p_sd, VLC_THREAD_PRIORITY_LOW ) )
     {
-        TAB_CLEAN( p_sys->i_query, p_sys->ppsz_query );
         goto error;
     }
     return VLC_SUCCESS;
@@ -259,13 +261,8 @@ void Close_LuaSD( vlc_object_t *p_this )
     services_discovery_t *p_sd = ( services_discovery_t * )p_this;
     services_discovery_sys_t *p_sys = p_sd->p_sys;
 
-    vlc_cancel( p_sys->thread );
+    vlc_queue_Kill( &p_sys->queue, &p_sys->dead );
     vlc_join( p_sys->thread, NULL );
-
-    for( int i = 0; i < p_sys->i_query; i++ )
-        free( p_sys->ppsz_query[i] );
-    TAB_CLEAN( p_sys->i_query, p_sys->ppsz_query );
-
     free( p_sys->psz_filename );
     lua_close( p_sys->L );
     free( p_sys );
@@ -280,8 +277,6 @@ static void* Run( void *data )
     services_discovery_sys_t *p_sys = p_sd->p_sys;
     lua_State *L = p_sys->L;
 
-    int cancel = vlc_savecancel();
-
     lua_getglobal( L, "main" );
     if( !lua_isfunction( L, lua_gettop( L ) ) || lua_pcall( L, 0, 1, 0 ) )
     {
@@ -289,7 +284,6 @@ static void* Run( void *data )
                   "function main(): %s", p_sys->psz_filename,
                   lua_tostring( L, lua_gettop( L ) ) );
         lua_pop( L, 1 );
-        vlc_restorecancel( cancel );
         return NULL;
     }
     msg_Dbg( p_sd, "LuaSD script loaded: %s", p_sys->psz_filename );
@@ -298,37 +292,20 @@ static void* Run( void *data )
      * open, but lua will never gc until lua_close(). */
     lua_gc( L, LUA_GCCOLLECT, 0 );
 
-    vlc_restorecancel( cancel );
-
     /* Main loop to handle search requests */
-    vlc_mutex_lock( &p_sys->lock );
-    mutex_cleanup_push( &p_sys->lock );
-    for( ;; )
-    {
-        /* Wait for a request */
-        if( !p_sys->i_query )
-        {
-            vlc_cond_wait( &p_sys->cond, &p_sys->lock );
-            continue;
-        }
-
-        /* Execute one query (protected against cancellation) */
-        char *psz_query = p_sys->ppsz_query[p_sys->i_query - 1];
-        TAB_ERASE(p_sys->i_query, p_sys->ppsz_query, p_sys->i_query - 1);
-        vlc_mutex_unlock( &p_sys->lock );
+    struct sd_query *query;
 
-        cancel = vlc_savecancel();
-        DoSearch( p_sd, psz_query );
-        free( psz_query );
+    while( (query = vlc_queue_DequeueKillable( &p_sys->queue,
+                                               &p_sys->dead )) != NULL )
+    {
+        /* Execute one query */
+        DoSearch( p_sd, query->query );
+        free( query );
         /* Force garbage collection, because the core will keep the SD
          * open, but lua will never gc until lua_close(). */
         lua_gc( L, LUA_GCCOLLECT, 0 );
-        vlc_restorecancel( cancel );
-
-        vlc_mutex_lock( &p_sys->lock );
     }
-    vlc_cleanup_pop();
-    vlc_assert_unreachable();
+    return NULL;
 }
 
 /*****************************************************************************
@@ -343,10 +320,15 @@ static int Control( services_discovery_t *p_sd, int i_command, va_list args )
     case SD_CMD_SEARCH:
     {
         const char *psz_query = va_arg( args, const char * );
-        vlc_mutex_lock( &p_sys->lock );
-        TAB_APPEND( p_sys->i_query, p_sys->ppsz_query, strdup( psz_query ) );
-        vlc_cond_signal( &p_sys->cond );
-        vlc_mutex_unlock( &p_sys->lock );
+        size_t len = strlen(psz_query) + 1;
+        struct sd_query *query = malloc(sizeof (*query) + len);
+
+        if (unlikely(query == NULL))
+            return VLC_ENOMEM;
+
+        query->next = NULL;
+        memcpy(query->query, psz_query, len);
+        vlc_queue_Enqueue(&p_sys->queue, query);
         break;
     }