libmatroska2: Add variant of MATROSKA_GetBlockForTimecode

The differences of MATROSKA_GetNextBlockForTimecode and the classical MATROSKA_GetBlockForTimecode are threefold: 1. The new function can return both the inner Block as well as the outer BlockGroup based upon a parameter (that is irrelevant for SimpleBlocks). 2. Consequently the return value is a pointer to an ebml_element and no longer a matroska_block*. 3. It also allows to get a matching block that is not the first matching block in a cluster. This commit is in preparation of a patch for mkvalidator. Signed-off-by: Andreas Rheinhardt <[email protected]>
Matroska-Org · Feb 7, 2019 · 4667ef8 · 4667ef8
1 parent 374b3c9
commit 4667ef8
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Showing 2 changed files with 10 additions and 4 deletions.
diff --git a/libmatroska2/matroska/matroska.h b/libmatroska2/matroska/matroska.h
@@ -192,6 +192,7 @@ EBML_DLL err_t MATROSKA_BlockGetFrame(const matroska_block *Block, size_t FrameN
 EBML_DLL err_t MATROSKA_BlockAppendFrame(matroska_block *Block, const matroska_frame *Frame, timecode_t ClusterTimecode);
 
 
+EBML_DLL ebml_element *MATROSKA_GetNextBlockForTimecode(matroska_cluster *Cluster, const ebml_element *Current, timecode_t Timecode, int16_t Track, int Outer);
 EBML_DLL matroska_block *MATROSKA_GetBlockForTimecode(matroska_cluster *Cluster, timecode_t Timecode, int16_t Track);
 EBML_DLL void MATROSKA_LinkClusterBlocks(matroska_cluster *Cluster, ebml_master *RSegmentInfo, ebml_master *Tracks, bool_t KeepUnmatched);
 

diff --git a/libmatroska2/matroskamain.c b/libmatroska2/matroskamain.c
@@ -789,10 +789,10 @@ err_t MATROSKA_CuePointUpdate(matroska_cuepoint *Cue, ebml_element *Segment)
     return ERR_NONE;
 }
 
-matroska_block *MATROSKA_GetBlockForTimecode(matroska_cluster *Cluster, timecode_t Timecode, int16_t Track)
+ebml_element *MATROSKA_GetNextBlockForTimecode(matroska_cluster *Cluster, const ebml_element *Current, timecode_t Timecode, int16_t Track, int Outer)
 {
     ebml_element *Block, *GBlock;
-    for (Block = EBML_MasterChildren(Cluster);Block;Block=EBML_MasterNext(Block))
+    for (Block = Current ? EBML_MasterNext(Current) : EBML_MasterChildren(Cluster); Block; Block = EBML_MasterNext(Block))
     {
         if (EBML_ElementIsType(Block, &MATROSKA_ContextBlockGroup))
         {
@@ -803,7 +803,7 @@ matroska_block *MATROSKA_GetBlockForTimecode(matroska_cluster *Cluster, timecode
                     if (MATROSKA_BlockTrackNum((matroska_block*)GBlock) == Track &&
                         MATROSKA_BlockTimecode((matroska_block*)GBlock) == Timecode)
                     {
-                        return (matroska_block*)GBlock;
+                        return Outer ? Block : GBlock;
                     }
                 }
             }
@@ -813,13 +813,18 @@ matroska_block *MATROSKA_GetBlockForTimecode(matroska_cluster *Cluster, timecode
             if (MATROSKA_BlockTrackNum((matroska_block*)Block) == Track &&
                 MATROSKA_BlockTimecode((matroska_block*)Block) == Timecode)
             {
-                return (matroska_block*)Block;
+                return Block;
             }
         }
     }
     return NULL;
 }
 
+matroska_block *MATROSKA_GetBlockForTimecode(matroska_cluster *Cluster, timecode_t Timecode, int16_t Track)
+{
+    return (matroska_block*)MATROSKA_GetNextBlockForTimecode(Cluster, NULL, Timecode, Track, 0);
+}
+
 void MATROSKA_LinkClusterBlocks(matroska_cluster *Cluster, ebml_master *RSegmentInfo, ebml_master *Tracks, bool_t KeepUnmatched)
 {
     ebml_element *Block, *GBlock,*NextBlock;