2 files changed, 51 insertions, 12 deletions

diff --git a/source/core/slang-riff.cpp b/source/core/slang-riff.cpp
index 9fc23fbc8..2162c40be 100644
--- a/source/core/slang-riff.cpp
+++ b/source/core/slang-riff.cpp
@@ -313,6 +313,11 @@ struct DumpVisitor : public RiffContainer::Visitor
     return SLANG_OK;
 }
 
+/* static */SlangResult RiffUtil::write(RiffContainer* container, Stream* stream)
+{
+    return write(container->getRoot(), true, stream);
+}
+
 /* static */SlangResult RiffUtil::read(Stream* stream, RiffContainer& outContainer)
 {
     typedef RiffContainer::ScopeChunk ScopeChunk;
@@ -561,6 +566,20 @@ void RiffContainer::ListChunk::findContained(FourCC type, List<DataChunk*>& out)
     }
 }
 
+RiffContainer::ListChunk* RiffContainer::ListChunk::findContainedList(FourCC type)
+{
+    Chunk* chunk = m_containedChunks;
+    while (chunk)
+    {
+        if (chunk->m_fourCC == type && chunk->m_kind == Chunk::Kind::List)
+        {
+            return static_cast<ListChunk*>(chunk);
+        }
+        chunk = chunk->m_next;
+    }
+    return nullptr;
+}
+
 RiffContainer::Data* RiffContainer::ListChunk::findContainedData(FourCC type) const
 {
     Chunk* found = findContained(type);
@@ -841,11 +860,11 @@ void RiffContainer::setPayload(Data* data, const void* payload, size_t size)
 
     // Add current chunks data
     m_dataChunk->m_payloadSize += size;
-
+    
     data->m_ownership = Ownership::Arena;
     data->m_size = size;
 
-    data->m_payload = m_arena.allocate(size);
+    data->m_payload = m_arena.allocateAligned(size, PAYLOAD_MIN_ALIGNMENT);
 
     if (payload)
     {
@@ -922,7 +941,7 @@ RiffContainer::Data* RiffContainer::makeSingleData(DataChunk* dataChunk)
         // Okay lets combine all into one block
         const size_t payloadSize = dataChunk->calcPayloadSize();
 
-        void* dst = m_arena.allocate(payloadSize);
+        void* dst = m_arena.allocateAligned(payloadSize, PAYLOAD_MIN_ALIGNMENT);
         dataChunk->getPayload(dst);
 
         // Remove other datas
diff --git a/source/core/slang-riff.h b/source/core/slang-riff.h
index 9bdbcfdeb..43c5e285d 100644
--- a/source/core/slang-riff.h
+++ b/source/core/slang-riff.h
@@ -177,6 +177,14 @@ need to be recalculated, before serialization.
 class RiffContainer
 {
 public:
+    enum 
+    {
+        // This alignment is only made for arena based allocations.
+        // For external blocks it's client code to have appropriate alignment.
+        // This is needed because when reading a RiffContainer, all allocation is arena based, and
+        // if the payload contains 8 byte aligned data, the overall payload needs to be 8 byte aligned.
+        PAYLOAD_MIN_ALIGNMENT = 8,
+    };
 
     enum class Ownership
     {
@@ -186,10 +194,6 @@ public:
         Owned,              ///< It's owned, but wasn't allocated on the arena
     };
 
-    struct ListChunk;
-    struct DataChunk;
-
-    
     struct Data
     {
             /// Get the payload
@@ -214,8 +218,11 @@ public:
     };
 
     struct Chunk;
-    typedef SlangResult(*VisitorCallback)(Chunk* chunk, void* data);
+    struct ListChunk;
+    struct DataChunk;
 
+    typedef SlangResult(*VisitorCallback)(Chunk* chunk, void* data);
+    
     class Visitor;
     struct Chunk
     {
@@ -270,6 +277,8 @@ public:
 
         void* findContainedData(FourCC type, size_t minSize) const;
 
+        ListChunk* findContainedList(FourCC type);
+
             /// Finds the contained data. NOTE! Assumes that there is only as single data block, and will return nullptr if there is not
         Data* findContainedData(FourCC type) const;
 
@@ -291,6 +300,9 @@ public:
             /// Get the sub type
         FourCC getSubType() const { return m_fourCC; }
 
+            /// A singly linked list of contained chunks directly contained in this chunk
+        Chunk* getFirstContainedChunk() const { return m_containedChunks; }
+
         Chunk* m_containedChunks;               ///< The contained chunks
         Chunk* m_endChunk;                      ///< The last chunk (only set when pushed, and used when popped)
     };
@@ -416,9 +428,14 @@ protected:
 template <typename T>
 T* as(RiffContainer::Chunk* chunk)
 {
-    return T::isType(chunk) ? static_cast<T*>(chunk) : nullptr;
+    return chunk && T::isType(chunk) ? static_cast<T*>(chunk) : nullptr;
+}
+// -----------------------------------------------------------------------------
+template <typename T>
+T* as(RiffContainer::Chunk* chunk, FourCC fourCC)
+{
+    return chunk && chunk->m_fourCC == fourCC && T::isType(chunk) ? static_cast<T*>(chunk) : nullptr;
 }
-
 
 struct RiffUtil
 {
@@ -449,8 +466,11 @@ struct RiffUtil
         /// Get the size taking into account padding
     static size_t getPadSize(size_t in) { return (in + kRiffPadMask) & ~size_t(kRiffPadMask); }
 
-        /// Write a container and contents to a stream
-    static SlangResult write(ListChunk* container, bool isRoot, Stream* stream);
+        /// Write a chunk list and contents to a stream
+    static SlangResult write(ListChunk* listChunk, bool isRoot, Stream* stream);
+        /// Write a container to the stream
+    static SlangResult write(RiffContainer* container, Stream* stream);
+
         /// Read the stream into the container
     static SlangResult read(Stream* stream, RiffContainer& outContainer);
 };