New approach for slicing classes and exceptions

CHANGELOG-3.8.md

@@ -12,6 +12,11 @@ These are the changes since the Ice 3.7.10 release in [CHANGELOG-3.7.md](./CHANG
 
 ## Slice Language Changes
 
+- Removed support for the `["preserve-slice"]` metadata. Slice classes encoded in the Sliced-format are now always
+  full-preserved.
+
+- Exceptions are now always encoded in the Sliced-format and no longer support preservation of unknown type slices.
+
 - Removed local Slice. `local` is no longer a Slice keyword.
 
 - Slice classes can no longer define operations or implement interfaces, and `implements` is no longer a Slice keyword.

config/Make.rules.Darwin

@@ -35,7 +35,7 @@ endif
 shared_cppflags = $(if $(filter-out program,$($1_target)),-fPIC) -fvisibility=hidden
 
 cppflags        = -Wall -Wextra -Wshadow -Wshadow-all -Wredundant-decls -Wno-shadow-field \
-                  -Wdeprecated -Wstrict-prototypes -Werror -Wconversion -Wdocumentation -pthread \
+                  -Wdeprecated -Wstrict-prototypes -Wconversion -Wdocumentation -pthread \
                   $(if $(filter yes,$(OPTIMIZE)),-O2 -DNDEBUG,-g)
 
 ifeq ($(MAXWARN),yes)

cpp/include/Ice/Exception.h

@@ -10,7 +10,6 @@
 #include <Ice/Format.h>
 #include <Ice/ObjectF.h>
 #include <Ice/ValueF.h>
-#include <Ice/SlicedDataF.h>
 
 namespace Ice
 {
@@ -64,8 +63,6 @@ class ICE_API UserException : public IceUtil::Exception
      */
     std::unique_ptr<UserException> ice_clone() const;
 
-    virtual Ice::SlicedDataPtr ice_getSlicedData() const;
-
     /**
      * Obtains the Slice type ID of this exception.
      * @return The fully-scoped type ID.

cpp/include/Ice/InputStream.h

@@ -312,14 +312,12 @@ class ICE_API InputStream : public IceInternal::Buffer
     /**
      * Marks the end of a class instance.
      *
-     * @param preserve Pass true and the stream will preserve the unknown slices of the instance, or false
-     * to discard the unknown slices.
      * @return An object that encapsulates the unknown slice data.
      */
-    SlicedDataPtr endValue(bool preserve)
+    SlicedDataPtr endValue()
     {
         assert(_currentEncaps && _currentEncaps->decoder);
-        return _currentEncaps->decoder->endInstance(preserve);
+        return _currentEncaps->decoder->endInstance();
     }
 
     /**
@@ -333,15 +331,11 @@ class ICE_API InputStream : public IceInternal::Buffer
 
     /**
      * Marks the end of a user exception.
-     *
-     * @param preserve Pass true and the stream will preserve the unknown slices of the exception, or false
-     * to discard the unknown slices.
-     * @return An object that encapsulates the unknown slice data.
      */
-    SlicedDataPtr endException(bool preserve)
+    void endException()
     {
         assert(_currentEncaps && _currentEncaps->decoder);
-        return _currentEncaps->decoder->endInstance(preserve);
+        _currentEncaps->decoder->endInstance();
     }
 
     /**
@@ -1097,7 +1091,7 @@ class ICE_API InputStream : public IceInternal::Buffer
         virtual void throwException(UserExceptionFactory) = 0;
 
         virtual void startInstance(SliceType) = 0;
-        virtual SlicedDataPtr endInstance(bool) = 0;
+        virtual SlicedDataPtr endInstance() = 0;
         virtual std::string_view startSlice() = 0;
         virtual void endSlice() = 0;
         virtual void skipSlice() = 0;
@@ -1172,7 +1166,7 @@ class ICE_API InputStream : public IceInternal::Buffer
         virtual void throwException(UserExceptionFactory);
 
         virtual void startInstance(SliceType);
-        virtual SlicedDataPtr endInstance(bool);
+        virtual SlicedDataPtr endInstance();
         virtual std::string_view startSlice();
         virtual void endSlice();
         virtual void skipSlice();
@@ -1207,7 +1201,7 @@ class ICE_API InputStream : public IceInternal::Buffer
         virtual void throwException(UserExceptionFactory);
 
         virtual void startInstance(SliceType);
-        virtual SlicedDataPtr endInstance(bool);
+        virtual SlicedDataPtr endInstance();
         virtual std::string_view startSlice();
         virtual void endSlice();
         virtual void skipSlice();

cpp/include/Ice/OutputStream.h

@@ -161,13 +161,11 @@ class ICE_API OutputStream : public IceInternal::Buffer
 
     /**
      * Marks the start of an exception instance.
-     * @param data Contains the marshaled form of unknown slices from this instance. If not nil,
-     * these slices will be marshaled with the instance.
      */
-    void startException(const SlicedDataPtr& data)
+    void startException()
     {
         assert(_currentEncaps && _currentEncaps->encoder);
-        _currentEncaps->encoder->startInstance(ExceptionSlice, data);
+        _currentEncaps->encoder->startInstance(ExceptionSlice, nullptr);
     }
 
     /**

cpp/include/Ice/SlicedData.h

@@ -81,13 +81,6 @@ class ICE_API UnknownSlicedValue : public Value
      */
     UnknownSlicedValue(const std::string& unknownTypeId);
 
-    /**
-     * Obtains the sliced data associated with this instance.
-     * @return The sliced data if the value has a preserved-slice base class and has been sliced during
-     * unmarshaling of the value, or nil otherwise.
-     */
-    virtual SlicedDataPtr ice_getSlicedData() const override;
-
     /**
      * Determine the Slice type ID associated with this instance.
      * @return The type ID supplied to the constructor.
@@ -103,11 +96,6 @@ class ICE_API UnknownSlicedValue : public Value
         return std::static_pointer_cast<UnknownSlicedValue>(_iceCloneImpl());
     }
 
-    /// \cond STREAM
-    virtual void _iceWrite(::Ice::OutputStream*) const override;
-    virtual void _iceRead(::Ice::InputStream*) override;
-    /// \endcond
-
 protected:
 
     /// \cond INTERNAL
@@ -117,7 +105,6 @@ class ICE_API UnknownSlicedValue : public Value
 private:
 
     const std::string _unknownTypeId;
-    SlicedDataPtr _slicedData;
 };
 
 }

cpp/include/Ice/Value.h

@@ -76,7 +76,7 @@ class ICE_API Value
      * @return The sliced data if the value has a preserved-slice base class and has been sliced during
      * unmarshaling of the value, nil otherwise.
      */
-    virtual SlicedDataPtr ice_getSlicedData() const;
+    SlicedDataPtr ice_getSlicedData() const;
 
     /// \cond STREAM
     virtual void _iceWrite(Ice::OutputStream*) const;
@@ -93,6 +93,10 @@ class ICE_API Value
     virtual void _iceWriteImpl(Ice::OutputStream*) const {}
     virtual void _iceReadImpl(Ice::InputStream*) {}
     /// \endcond
+
+private:
+
+    ::std::shared_ptr<Ice::SlicedData> _slicedData;
 };
 
 /// \cond INTERNAL

cpp/src/Ice/Exception.cpp

@@ -97,16 +97,10 @@ Ice::UserException::ice_clone() const
     return unique_ptr<UserException>(static_cast<UserException*>(ice_cloneImpl()));
 }
 
-Ice::SlicedDataPtr
-Ice::UserException::ice_getSlicedData() const
-{
-    return nullptr;
-}
-
 void
 Ice::UserException::_write(::Ice::OutputStream* os) const
 {
-    os->startException(0);
+    os->startException();
     _writeImpl(os);
     os->endException();
 }
@@ -116,7 +110,7 @@ Ice::UserException::_read(::Ice::InputStream* is)
 {
     is->startException();
     _readImpl(is);
-    is->endException(false);
+    is->endException();
 }
 
 bool

cpp/src/Ice/InputStream.cpp

@@ -1880,7 +1880,7 @@ Ice::InputStream::EncapsDecoder10::startInstance(SliceType)
 }
 
 SlicedDataPtr
-Ice::InputStream::EncapsDecoder10::endInstance(bool)
+Ice::InputStream::EncapsDecoder10::endInstance()
 {
     //
     // Read the Ice::Value slice.
@@ -2182,15 +2182,11 @@ Ice::InputStream::EncapsDecoder11::startInstance(SliceType)
 }
 
 SlicedDataPtr
-Ice::InputStream::EncapsDecoder11::endInstance(bool preserve)
+Ice::InputStream::EncapsDecoder11::endInstance()
 {
-    SlicedDataPtr slicedData;
-    if (preserve)
-    {
-        slicedData = readSlicedData();
-    }
-    _current->slices.clear();
+    SlicedDataPtr slicedData = readSlicedData();
     _current->indirectionTables.clear();
+    _current->slices.clear();
     _current = _current->previous;
     return slicedData;
 }
@@ -2337,36 +2333,37 @@ Ice::InputStream::EncapsDecoder11::skipSlice()
     }
 
     //
-    // Preserve this slice.
+    // Preserve this slice if unmarshalling a value in Slice format. Exception slices are not preserved.
     //
-    SliceInfoPtr info = make_shared<SliceInfo>();
-    info->typeId = _current->typeId;
-    info->compactId = _current->compactId;
-    info->hasOptionalMembers = _current->sliceFlags & FLAG_HAS_OPTIONAL_MEMBERS;
-    info->isLastSlice = _current->sliceFlags & FLAG_IS_LAST_SLICE;
-    if (info->hasOptionalMembers)
-    {
-        //
-        // Don't include the optional member end marker. It will be re-written by
-        // endSlice when the sliced data is re-written.
-        //
-        vector<uint8_t>(start, _stream->i - 1).swap(info->bytes);
-    }
-    else
+    if (_current->sliceType == ValueSlice)
     {
-        vector<uint8_t>(start, _stream->i).swap(info->bytes);
+        SliceInfoPtr info = make_shared<SliceInfo>();
+        info->typeId = _current->typeId;
+        info->compactId = _current->compactId;
+        info->hasOptionalMembers = _current->sliceFlags & FLAG_HAS_OPTIONAL_MEMBERS;
+        info->isLastSlice = _current->sliceFlags & FLAG_IS_LAST_SLICE;
+        if (info->hasOptionalMembers)
+        {
+            //
+            // Don't include the optional member end marker. It will be re-written by
+            // endSlice when the sliced data is re-written.
+            //
+            vector<uint8_t>(start, _stream->i - 1).swap(info->bytes);
+        }
+        else
+        {
+            vector<uint8_t>(start, _stream->i).swap(info->bytes);
+        }
+        _current->slices.push_back(info);
     }
 
     _current->indirectionTables.push_back(IndexList());
 
     //
     // Read the indirect object table. We read the instances or their
-    // IDs if the instance is a reference to an already un-marhsaled
+    // IDs if the instance is a reference to an already un-marshaled
     // object.
     //
-    // The SliceInfo object sequence is initialized only if
-    // readSlicedData is called.
-    //
     if (_current->sliceFlags & FLAG_HAS_INDIRECTION_TABLE)
     {
         IndexList& table = _current->indirectionTables.back();
@@ -2376,8 +2373,6 @@ Ice::InputStream::EncapsDecoder11::skipSlice()
             *p = readInstance(_stream->readSize(), 0, 0);
         }
     }
-
-    _current->slices.push_back(info);
 }
 
 bool

cpp/src/Ice/OutgoingAsync.cpp

@@ -958,7 +958,7 @@ LambdaInvoke::handleException(std::exception_ptr) noexcept
 bool
 LambdaInvoke::handleResponse(bool)
 {
-    return _response != nullptr;
+    return (_response) != nullptr;
 }
 
 void

cpp/src/Ice/OutputStream.cpp

@@ -850,6 +850,8 @@ void
 Ice::OutputStream::writeException(const UserException& e)
 {
     initEncaps();
+    // Exceptions are always encoded with the sliced format.
+    _currentEncaps->format = FormatType::SlicedFormat;
     _currentEncaps->encoder->write(e);
 }
 

cpp/src/Ice/RequestHandlerCache.cpp

@@ -329,4 +329,6 @@ RequestHandlerCache::handleException(
         assert(false);
         return 0;
     }
+    assert(false);
+    return 0;
 }

cpp/src/Ice/SlicedData.cpp

@@ -36,12 +36,6 @@ Ice::UnknownSlicedValue::UnknownSlicedValue(const string& unknownTypeId) : _unkn
 {
 }
 
-SlicedDataPtr
-Ice::UnknownSlicedValue::ice_getSlicedData() const
-{
-    return _slicedData;
-}
-
 string
 Ice::UnknownSlicedValue::ice_id() const
 {
@@ -53,17 +47,3 @@ Ice::UnknownSlicedValue::_iceCloneImpl() const
 {
     return make_shared<UnknownSlicedValue>(static_cast<const UnknownSlicedValue&>(*this));
 }
-
-void
-Ice::UnknownSlicedValue::_iceWrite(Ice::OutputStream* ostr) const
-{
-    ostr->startValue(_slicedData);
-    ostr->endValue();
-}
-
-void
-Ice::UnknownSlicedValue::_iceRead(Ice::InputStream* istr)
-{
-    istr->startValue();
-    _slicedData = istr->endValue(true);
-}

cpp/src/Ice/Value.cpp

@@ -25,7 +25,7 @@ Ice::Value::ice_postUnmarshal()
 void
 Ice::Value::_iceWrite(Ice::OutputStream* os) const
 {
-    os->startValue(0);
+    os->startValue(_slicedData);
     _iceWriteImpl(os);
     os->endValue();
 }
@@ -35,7 +35,7 @@ Ice::Value::_iceRead(Ice::InputStream* is)
 {
    is->startValue();
    _iceReadImpl(is);
-   is->endValue(false);
+   _slicedData = is->endValue();
 }
 
 string
@@ -54,7 +54,7 @@ Ice::Value::ice_staticId()
 SlicedDataPtr
 Ice::Value::ice_getSlicedData() const
 {
-    return nullptr;
+    return _slicedData;
 }
 
 std::shared_ptr<Ice::Value>