[vlc-devel] [PATCH 02/11] [RFC] core: add demux-filter objects to intercept & filter demuxer calls
Steve Lhomme
robux4 at videolabs.io
Mon May 2 18:24:01 CEST 2016
This can be used to tweak the results of some Control() calls or delay the
actual Demux() call.
---
NEWS | 3 ++
include/vlc_common.h | 2 ++
include/vlc_demux.h | 47 ++++++++++++++++++++++++-
src/input/demux.c | 98 ++++++++++++++++++++++++++++++++++++++++++++++++++--
src/input/input.c | 16 +++++++++
src/input/var.c | 1 +
src/libvlc-module.c | 5 +++
src/libvlc.c | 2 ++
8 files changed, 171 insertions(+), 3 deletions(-)
diff --git a/NEWS b/NEWS
index dd37984..9da578c 100644
--- a/NEWS
+++ b/NEWS
@@ -99,6 +99,9 @@ Stream filter:
* Added stream prebuffering plugin
* Removed HTTP Live streaming stream filter
* Added zlib (a.k.a. deflate) decompression filter
+
+Demux filter:
+ * Added a demuxer filter chain to filter or intercept control commands and demuxing
Audio output:
* Complete rewrite of the AudioTrack Android module. This is now the default.
diff --git a/include/vlc_common.h b/include/vlc_common.h
index f05d9c6..f61eb4e 100644
--- a/include/vlc_common.h
+++ b/include/vlc_common.h
@@ -227,6 +227,8 @@ typedef struct stream_t stream_t;
typedef struct stream_sys_t stream_sys_t;
typedef struct demux_t demux_t;
typedef struct demux_sys_t demux_sys_t;
+typedef struct demux_filter_t demux_filter_t;
+typedef struct demux_filter_sys_t demux_filter_sys_t;
typedef struct es_out_t es_out_t;
typedef struct es_out_id_t es_out_id_t;
typedef struct es_out_sys_t es_out_sys_t;
diff --git a/include/vlc_demux.h b/include/vlc_demux.h
index 45f5416..2d0ecf3 100644
--- a/include/vlc_demux.h
+++ b/include/vlc_demux.h
@@ -74,11 +74,31 @@ struct demux_t
int i_seekpoint; /* idem, start from 0 */
} info;
demux_sys_t *p_sys;
+ demux_filter_t *p_filters; /* chained list of demux-filters */
/* Weak link to parent input */
input_thread_t *p_input;
};
+struct demux_filter_t
+{
+ VLC_COMMON_MEMBERS
+
+ /* Module properties */
+ module_t *p_module;
+
+ /* return true if the demux should return the returned code */
+ int (*pf_demux) ( demux_filter_t * );
+ int (*pf_control)( demux_filter_t *, int i_query, va_list args);
+
+ demux_t *p_demux;
+ demux_filter_sys_t *p_sys;
+
+ const config_chain_t *p_cfg;
+
+ struct demux_filter_t *p_next;
+};
+
/* pf_demux return values */
#define VLC_DEMUXER_EOF 0
#define VLC_DEMUXER_EGENERIC -1
@@ -296,12 +316,25 @@ VLC_API int demux_vaControlHelper( stream_t *, int64_t i_start, int64_t i_end,
VLC_USED static inline int demux_Demux( demux_t *p_demux )
{
- if( !p_demux->pf_demux )
+ if( !p_demux->pf_demux && !p_demux->p_filters )
return 1;
+ if ( p_demux->p_filters != NULL )
+ return p_demux->p_filters->pf_demux( p_demux->p_filters );
+
return p_demux->pf_demux( p_demux );
}
+VLC_USED static inline int demux_FilterDemux( demux_filter_t *p_demux_filter )
+{
+ if ( p_demux_filter->p_next )
+ return p_demux_filter->p_next->pf_demux( p_demux_filter->p_next );
+
+ if ( p_demux_filter->p_demux )
+ return p_demux_filter->p_demux->pf_demux( p_demux_filter->p_demux );
+ return 1;
+}
+
VLC_API int demux_vaControl( demux_t *p_demux, int i_query, va_list args );
static inline int demux_Control( demux_t *p_demux, int i_query, ... )
@@ -315,6 +348,16 @@ static inline int demux_Control( demux_t *p_demux, int i_query, ... )
return i_result;
}
+VLC_USED static inline int demux_FilterControl( demux_filter_t *p_demux_filter, int i_query, va_list args )
+{
+ if ( p_demux_filter->p_next )
+ return p_demux_filter->p_next->pf_control( p_demux_filter->p_next, i_query, args );
+
+ if ( p_demux_filter->p_demux )
+ return p_demux_filter->p_demux->pf_control( p_demux_filter->p_demux, i_query, args );
+ return 1;
+}
+
/*************************************************************************
* Miscellaneous helpers for demuxers
*************************************************************************/
@@ -395,6 +438,8 @@ VLC_API void demux_PacketizerDestroy( decoder_t *p_packetizer );
if( !p_demux->p_sys ) return VLC_ENOMEM;\
} while(0)
+demux_filter_t *demux_FilterChainNew( demux_t *p_demux, const char *psz_name );
+
/**
* @}
*/
diff --git a/src/input/demux.c b/src/input/demux.c
index 303c0b8..67a8646 100644
--- a/src/input/demux.c
+++ b/src/input/demux.c
@@ -363,7 +363,10 @@ static int demux_ControlInternal( demux_t *demux, int query, ... )
va_list ap;
va_start( ap, query );
- ret = demux->pf_control( demux, query, ap );
+ if ( demux->p_filters )
+ ret = demux->p_filters->pf_control( demux->p_filters, query, ap );
+ else
+ ret = demux->pf_control( demux, query, ap );
va_end( ap );
return ret;
}
@@ -382,7 +385,10 @@ int demux_vaControl( demux_t *demux, int query, va_list args )
va_list ap;
va_copy( ap, args );
- ret = demux->pf_control( demux, query, args );
+ if ( demux->p_filters )
+ ret = demux->p_filters->pf_control( demux->p_filters, query, args );
+ else
+ ret = demux->pf_control( demux, query, args );
if( ret != VLC_SUCCESS )
ret = stream_vaControl( demux->s, query, ap );
va_end( ap );
@@ -416,6 +422,8 @@ int demux_vaControl( demux_t *demux, int query, va_list args )
}
}
+ if ( demux->p_filters )
+ return demux->p_filters->pf_control( demux->p_filters, query, args );
return demux->pf_control( demux, query, args );
}
@@ -656,3 +664,89 @@ static bool SkipAPETag( demux_t *p_demux )
return true;
}
+static demux_filter_t *demux_FilterNew( demux_t *p_demux, const char *p_name,
+ const config_chain_t *p_cfg )
+{
+ demux_filter_t *p_filter = vlc_custom_create( VLC_OBJECT(p_demux), sizeof( *p_filter ), "demux_filter" );
+ if( unlikely(p_filter == NULL) )
+ return NULL;
+
+ p_filter->p_demux = p_demux;
+ p_filter->p_cfg = p_cfg;
+ p_filter->p_module = module_need( p_filter, "demux_filter", p_name, true);
+ if( p_filter->p_module == NULL )
+ goto error;
+
+ return p_filter;
+
+error:
+ vlc_object_release( p_filter );
+ return NULL;
+}
+
+demux_filter_t *demux_FilterChainNew( demux_t *p_demux, const char *psz_chain )
+{
+ if( !psz_chain || !*psz_chain )
+ return NULL;
+
+ char *psz_parser = strdup(psz_chain);
+ if(!psz_parser)
+ return NULL;
+
+ vlc_array_t cfg, name;
+ vlc_array_init(&cfg);
+ vlc_array_init(&name);
+
+ /* parse chain */
+ while(psz_parser)
+ {
+ config_chain_t *p_cfg;
+ char *psz_name;
+ char *psz_rest_chain = config_ChainCreate( &psz_name, &p_cfg, psz_parser );
+ free( psz_parser );
+ psz_parser = psz_rest_chain;
+
+ vlc_array_append(&cfg, p_cfg);
+ vlc_array_append(&name, psz_name);
+ }
+
+ demux_filter_t *p_prev = NULL;
+ demux_filter_t *p_next = NULL;
+ int i = vlc_array_count(&name);
+ while (i--)
+ {
+ const char *p_name = vlc_array_item_at_index(&name, i);
+ p_next = demux_FilterNew( p_demux, p_name, vlc_array_item_at_index(&cfg, i) );
+ if ( p_next == NULL )
+ goto error;
+
+ p_next->p_next = p_prev;
+ p_prev = p_next;
+ }
+
+ vlc_array_clear(&name);
+ vlc_array_clear(&cfg);
+
+ return p_next;
+ error:
+ i++; /* last module couldn't be created */
+
+ /* destroy all modules created */
+ while(p_prev)
+ {
+ p_next = p_prev->p_next;
+ vlc_object_release( p_prev );
+ }
+
+ /* then destroy all names and config which weren't destroyed by
+ * sout_StreamDelete */
+ while(i--)
+ {
+ free(vlc_array_item_at_index(&name, i));
+ config_ChainDestroy(vlc_array_item_at_index(&cfg, i));
+ }
+ vlc_array_clear(&name);
+ vlc_array_clear(&cfg);
+
+ return NULL;
+}
diff --git a/src/input/input.c b/src/input/input.c
index 5591a4e..604fc2b 100644
--- a/src/input/input.c
+++ b/src/input/input.c
@@ -2193,6 +2193,14 @@ static input_source_t *InputSourceNew( input_thread_t *p_input,
return NULL;
}
+ char *psz_demux_chain = var_GetNonEmptyString(p_input, "demux-filter");
+ /* add the chain of demux filters */
+ demux_filter_t *p_filtered_demux = demux_FilterChainNew( in->p_demux, psz_demux_chain );
+ in->p_demux->p_filters = p_filtered_demux;
+ if ( p_filtered_demux == NULL && psz_demux_chain != NULL)
+ msg_Dbg( p_input, "Failed to create demux filter chain %s", psz_demux_chain );
+ free( psz_demux_chain );
+
/* Get infos from (access_)demux */
bool b_can_seek;
if( demux_Control( in->p_demux, DEMUX_CAN_SEEK, &b_can_seek ) )
@@ -2295,7 +2303,15 @@ static void InputSourceDestroy( input_source_t *in )
int i;
if( in->p_demux )
+ {
+ while (in->p_demux->p_filters )
+ {
+ demux_filter_t *p_old = in->p_demux->p_filters;
+ in->p_demux->p_filters = p_old->p_next;
+ vlc_object_release( p_old );
+ }
demux_Delete( in->p_demux );
+ }
if( in->i_title > 0 )
{
diff --git a/src/input/var.c b/src/input/var.c
index 0cc1217..080f358 100644
--- a/src/input/var.c
+++ b/src/input/var.c
@@ -505,6 +505,7 @@ void input_ConfigVarInit ( input_thread_t *p_input )
/* */
var_Create( p_input, "access", VLC_VAR_STRING | VLC_VAR_DOINHERIT );
var_Create( p_input, "demux", VLC_VAR_STRING | VLC_VAR_DOINHERIT );
+ var_Create( p_input, "demux-filter", VLC_VAR_STRING | VLC_VAR_DOINHERIT );
var_Create( p_input, "stream-filter", VLC_VAR_STRING | VLC_VAR_DOINHERIT );
/* Meta */
diff --git a/src/libvlc-module.c b/src/libvlc-module.c
index d529c32..4c9c462 100644
--- a/src/libvlc-module.c
+++ b/src/libvlc-module.c
@@ -985,6 +985,10 @@ static const char *const ppsz_prefres[] = {
#define STREAM_FILTER_LONGTEXT N_( \
"Stream filters are used to modify the stream that is being read. " )
+#define DEMUX_FILTER_TEXT N_("Demux filter module")
+#define DEMUX_FILTER_LONGTEXT N_( \
+ "Demux filters are used to modify/control the stream that is being read. " )
+
#define DEMUX_TEXT N_("Demux module")
#define DEMUX_LONGTEXT N_( \
"Demultiplexers are used to separate the \"elementary\" streams " \
@@ -1876,6 +1880,7 @@ vlc_module_begin ()
add_module_list( "stream-filter", "stream_filter", NULL,
STREAM_FILTER_TEXT, STREAM_FILTER_LONGTEXT, false )
+ add_string( "demux-filter", NULL, DEMUX_FILTER_TEXT, DEMUX_FILTER_LONGTEXT, true )
/* Stream output options */
set_category( CAT_SOUT )
diff --git a/src/libvlc.c b/src/libvlc.c
index 4e33a04..ccc62ca 100644
--- a/src/libvlc.c
+++ b/src/libvlc.c
@@ -409,6 +409,8 @@ dbus_out:
var_Create( p_libvlc, "app-version", VLC_VAR_STRING );
var_SetString( p_libvlc, "app-version", PACKAGE_VERSION );
+ var_Create( p_libvlc, "demux-filter", VLC_VAR_STRING | VLC_VAR_DOINHERIT );
+
/* System specific configuration */
system_Configure( p_libvlc, i_argc - vlc_optind, ppsz_argv + vlc_optind );
--
2.7.0
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