[vlc-devel] [RFC PATCH 1/2] decoder: rearrange module load/unload

[Thomas Guillem]

This will allow a decoder module to be loaded/unloaded more than one time.
---
 src/input/decoder.c | 134 ++++++++++++++++++++++++++++------------------------
 1 file changed, 73 insertions(+), 61 deletions(-)

diff --git a/src/input/decoder.c b/src/input/decoder.c
index 0fad3f9..49f67c9 100644
--- a/src/input/decoder.c
+++ b/src/input/decoder.c
@@ -135,6 +135,71 @@ struct decoder_owner_sys_t
 /* */
 #define DECODER_SPU_VOUT_WAIT_DURATION ((int)(0.200*CLOCK_FREQ))
 
+static void LoadDecoder( decoder_t *p_dec, bool b_packetizer,
+                         const es_format_t *p_fmt )
+{
+    p_dec->b_frame_drop_allowed = true;
+    p_dec->b_need_packetized = false;
+    p_dec->i_extra_picture_buffers = 0;
+    p_dec->p_description = NULL;
+
+    p_dec->pf_decode_audio = NULL;
+    p_dec->pf_decode_video = NULL;
+    p_dec->pf_decode_sub = NULL;
+    p_dec->pf_get_cc = NULL;
+    p_dec->pf_packetize = NULL;
+
+    es_format_Copy( &p_dec->fmt_in, p_fmt );
+    memset( &p_dec->fmt_out, 0, sizeof(es_format_t) );
+
+    /* Find a suitable decoder/packetizer module */
+    if( !b_packetizer )
+        p_dec->p_module = module_need( p_dec, "decoder", "$codec", false );
+    else
+        p_dec->p_module = module_need( p_dec, "packetizer", "$packetizer", false );
+
+    if( !p_dec->p_module )
+        es_format_Clean( &p_dec->fmt_in );
+}
+
+static void UnloadDecoder( decoder_t *p_dec )
+{
+    module_unneed( p_dec, p_dec->p_module );
+    p_dec->p_module = NULL;
+
+    if( p_dec->p_description )
+        vlc_meta_Delete( p_dec->p_description );
+
+    es_format_Clean( &p_dec->fmt_in );
+    es_format_Clean( &p_dec->fmt_out );
+}
+
+static void LoadPacketizer( decoder_t *p_dec )
+{
+    decoder_owner_sys_t *p_owner = p_dec->p_owner;
+
+    p_owner->p_packetizer =
+        vlc_custom_create( p_dec, sizeof( decoder_t ), "packetizer" );
+    if( !p_owner->p_packetizer )
+        return;
+
+    LoadDecoder( p_owner->p_packetizer, true, &p_dec->fmt_in );
+    if( !p_owner->p_packetizer->p_module )
+    {
+        vlc_object_release( p_owner->p_packetizer );
+        p_owner->p_packetizer = NULL;
+    }
+}
+
+static void UnloadPacketizer( decoder_t *p_dec )
+{
+    decoder_owner_sys_t *p_owner = p_dec->p_owner;
+
+    UnloadDecoder( p_owner->p_packetizer );
+    vlc_object_release( p_owner->p_packetizer );
+    p_owner->p_packetizer = NULL;
+}
+
 static void DecoderUpdateFormatLocked( decoder_t *p_dec )
 {
     decoder_owner_sys_t *p_owner = p_dec->p_owner;
@@ -1474,28 +1539,11 @@ static decoder_t * CreateDecoder( vlc_object_t *p_parent,
 {
     decoder_t *p_dec;
     decoder_owner_sys_t *p_owner;
-    es_format_t null_es_format;
 
     p_dec = vlc_custom_create( p_parent, sizeof( *p_dec ), "decoder" );
     if( p_dec == NULL )
         return NULL;
 
-    p_dec->b_frame_drop_allowed = true;
-    p_dec->pf_decode_audio = NULL;
-    p_dec->pf_decode_video = NULL;
-    p_dec->pf_decode_sub = NULL;
-    p_dec->pf_get_cc = NULL;
-    p_dec->pf_packetize = NULL;
-
-    /* Initialize the decoder */
-    p_dec->p_module = NULL;
-
-    memset( &null_es_format, 0, sizeof(es_format_t) );
-    es_format_Copy( &p_dec->fmt_in, fmt );
-    es_format_Copy( &p_dec->fmt_out, &null_es_format );
-
-    p_dec->p_description = NULL;
-
     /* Allocate our private structure for the decoder */
     p_dec->p_owner = p_owner = malloc( sizeof( decoder_owner_sys_t ) );
     if( unlikely(p_owner == NULL) )
@@ -1560,37 +1608,12 @@ static decoder_t * CreateDecoder( vlc_object_t *p_parent,
     p_dec->pf_get_display_rate = DecoderGetDisplayRate;
 
     /* Find a suitable decoder/packetizer module */
-    if( !b_packetizer )
-        p_dec->p_module = module_need( p_dec, "decoder", "$codec", false );
-    else
-        p_dec->p_module = module_need( p_dec, "packetizer", "$packetizer", false );
+    LoadDecoder( p_dec, b_packetizer, fmt );
 
     /* Check if decoder requires already packetized data */
     if( !b_packetizer &&
         p_dec->b_need_packetized && !p_dec->fmt_in.b_packetized )
-    {
-        p_owner->p_packetizer =
-            vlc_custom_create( p_parent, sizeof( decoder_t ), "packetizer" );
-        if( p_owner->p_packetizer )
-        {
-            es_format_Copy( &p_owner->p_packetizer->fmt_in,
-                            &p_dec->fmt_in );
-
-            es_format_Copy( &p_owner->p_packetizer->fmt_out,
-                            &null_es_format );
-
-            p_owner->p_packetizer->p_module =
-                module_need( p_owner->p_packetizer,
-                             "packetizer", "$packetizer", false );
-
-            if( !p_owner->p_packetizer->p_module )
-            {
-                es_format_Clean( &p_owner->p_packetizer->fmt_in );
-                vlc_object_release( p_owner->p_packetizer );
-                p_owner->p_packetizer = NULL;
-            }
-        }
-    }
+        LoadPacketizer( p_dec );
 
     /* Copy ourself the input replay gain */
     if( fmt->i_cat == AUDIO_ES )
@@ -1643,6 +1666,10 @@ static void DeleteDecoder( decoder_t * p_dec )
              (char*)&p_dec->fmt_in.i_codec,
              (unsigned)block_FifoCount( p_owner->p_fifo ) );
 
+    const bool b_flush_spu = p_dec->fmt_out.i_cat == SPU_ES;
+    if( p_dec->p_module )
+        UnloadDecoder( p_dec );
+
     /* Free all packets still in the decoder fifo. */
     block_FifoRelease( p_owner->p_fifo );
 
@@ -1677,7 +1704,7 @@ static void DeleteDecoder( decoder_t * p_dec )
 #endif
     es_format_Clean( &p_owner->fmt );
 
-    if( p_dec->fmt_out.i_cat == SPU_ES )
+    if( b_flush_spu )
     {
         vout_thread_t *p_vout = input_resource_HoldVout( p_owner->p_resource );
         if( p_vout )
@@ -1688,23 +1715,11 @@ static void DeleteDecoder( decoder_t * p_dec )
         }
     }
 
-    es_format_Clean( &p_dec->fmt_in );
-    es_format_Clean( &p_dec->fmt_out );
-    if( p_dec->p_description )
-        vlc_meta_Delete( p_dec->p_description );
     if( p_owner->p_description )
         vlc_meta_Delete( p_owner->p_description );
 
     if( p_owner->p_packetizer )
-    {
-        module_unneed( p_owner->p_packetizer,
-                       p_owner->p_packetizer->p_module );
-        es_format_Clean( &p_owner->p_packetizer->fmt_in );
-        es_format_Clean( &p_owner->p_packetizer->fmt_out );
-        if( p_owner->p_packetizer->p_description )
-            vlc_meta_Delete( p_owner->p_packetizer->p_description );
-        vlc_object_release( p_owner->p_packetizer );
-    }
+        UnloadPacketizer( p_dec );
 
     vlc_cond_destroy( &p_owner->wait_fifo );
     vlc_cond_destroy( &p_owner->wait_acknowledge );
@@ -1776,7 +1791,6 @@ static decoder_t *decoder_New( vlc_object_t *p_parent, input_thread_t *p_input,
     if( vlc_clone( &p_dec->p_owner->thread, DecoderThread, p_dec, i_priority ) )
     {
         msg_Err( p_dec, "cannot spawn decoder thread" );
-        module_unneed( p_dec, p_dec->p_module );
         DeleteDecoder( p_dec );
         return NULL;
     }
@@ -1833,8 +1847,6 @@ void input_DecoderDelete( decoder_t *p_dec )
 
     vlc_join( p_owner->thread, NULL );
 
-    module_unneed( p_dec, p_dec->p_module );
-
     /* */
     if( p_dec->p_owner->cc.b_supported )
     {
-- 
2.1.4