Complete refactoring, fix up IPC tests for flattened string/binary bu…

…ffer/metadata layout

Change-Id: I15e9f14bbfcd549f14436b67efcde62e20e83890

cpp/src/arrow/ipc/adapter.cc

@@ -78,22 +78,6 @@ static bool IsPrimitive(const DataType* type) {
   }
 }
 
-static bool IsListType(const DataType* type) {
-  DCHECK(type != nullptr);
-  switch (type->type) {
-    // TODO(emkornfield) grouping like this are used in a few places in the
-    // code consider using pattern like:
-    // http://stackoverflow.com/questions/26784685/c-macro-for-calling-function-based-on-enum-type
-    //
-    case Type::BINARY:
-    case Type::LIST:
-    case Type::STRING:
-      return true;
-    default:
-      return false;
-  }
-}
-
 // ----------------------------------------------------------------------
 // Record batch write path
 
@@ -115,7 +99,11 @@ Status VisitArray(const Array* arr, std::vector<flatbuf::FieldNode>* field_nodes
   if (IsPrimitive(arr_type)) {
     const auto prim_arr = static_cast<const PrimitiveArray*>(arr);
     buffers->push_back(prim_arr->data());
-  } else if (IsListType(arr_type)) {
+  } else if (arr->type_enum() == Type::STRING || arr->type_enum() == Type::BINARY) {
+    const auto binary_arr = static_cast<const BinaryArray*>(arr);
+    buffers->push_back(binary_arr->offsets());
+    buffers->push_back(binary_arr->data());
+  } else if (arr->type_enum() == Type::LIST) {
     const auto list_arr = static_cast<const ListArray*>(arr);
     buffers->push_back(list_arr->offset_buffer());
     RETURN_NOT_OK(VisitArray(
@@ -331,9 +319,21 @@ class RecordBatchReader::RecordBatchReaderImpl {
       }
       return MakePrimitiveArray(
           type, field_meta.length, data, field_meta.null_count, null_bitmap, out);
-    }
+    } else if (type->type == Type::STRING || type->type == Type::BINARY) {
+      std::shared_ptr<Buffer> offsets;
+      std::shared_ptr<Buffer> values;
+      RETURN_NOT_OK(GetBuffer(buffer_index_++, &offsets));
+      RETURN_NOT_OK(GetBuffer(buffer_index_++, &values));
 
-    if (IsListType(type.get())) {
+      if (type->type == Type::STRING) {
+        *out = std::make_shared<StringArray>(
+            field_meta.length, offsets, values, field_meta.null_count, null_bitmap);
+      } else {
+        *out = std::make_shared<BinaryArray>(
+            field_meta.length, offsets, values, field_meta.null_count, null_bitmap);
+      }
+      return Status::OK();
+    } else if (type->type == Type::LIST) {
       std::shared_ptr<Buffer> offsets;
       RETURN_NOT_OK(GetBuffer(buffer_index_++, &offsets));
       const int num_children = type->num_children();
@@ -346,11 +346,10 @@ class RecordBatchReader::RecordBatchReaderImpl {
       std::shared_ptr<Array> values_array;
       RETURN_NOT_OK(
           NextArray(type->child(0).get(), max_recursion_depth - 1, &values_array));
-      return MakeListArray(type, field_meta.length, offsets, values_array,
-          field_meta.null_count, null_bitmap, out);
-    }
-
-    if (type->type == Type::STRUCT) {
+      *out = std::make_shared<ListArray>(type, field_meta.length, offsets, values_array,
+          field_meta.null_count, null_bitmap);
+      return Status::OK();
+    } else if (type->type == Type::STRUCT) {
       const int num_children = type->num_children();
       std::vector<ArrayPtr> fields;
       fields.reserve(num_children);

cpp/src/arrow/type.h

@@ -288,7 +288,7 @@ struct ARROW_EXPORT StructType : public DataType {
 
 // These will be defined elsewhere
 template <typename T>
-struct type_traits {};
+struct TypeTraits {};
 
 }  // namespace arrow
 

cpp/src/arrow/types/construct.cc

@@ -121,16 +121,4 @@ Status MakePrimitiveArray(const TypePtr& type, int32_t length,
 #endif
 }
 
-Status MakeListArray(const TypePtr& type, int32_t length,
-    const std::shared_ptr<Buffer>& offsets, const ArrayPtr& values, int32_t null_count,
-    const std::shared_ptr<Buffer>& null_bitmap, ArrayPtr* out) {
-  *out =
-      std::make_shared<ListArray>(type, length, offsets, values, null_count, null_bitmap);
-#ifdef NDEBUG
-  return Status::OK();
-#else
-  return (*out)->Validate();
-#endif
-}
-
 }  // namespace arrow

cpp/src/arrow/types/construct.h

@@ -42,14 +42,6 @@ Status ARROW_EXPORT MakePrimitiveArray(const std::shared_ptr<DataType>& type,
     int32_t length, const std::shared_ptr<Buffer>& data, int32_t null_count,
     const std::shared_ptr<Buffer>& null_bitmap, std::shared_ptr<Array>* out);
 
-// Create new list arrays for logical types that are backed by ListArrays (e.g. list of
-// primitives and strings)
-// TODO(emkornfield) split up string vs list?
-Status ARROW_EXPORT MakeListArray(const std::shared_ptr<DataType>& type, int32_t length,
-    const std::shared_ptr<Buffer>& offests, const std::shared_ptr<Array>& values,
-    int32_t null_count, const std::shared_ptr<Buffer>& null_bitmap,
-    std::shared_ptr<Array>* out);
-
 }  // namespace arrow
 
 #endif  // ARROW_BUILDER_H_

cpp/src/arrow/types/primitive-test.cc

@@ -259,7 +259,7 @@ TYPED_TEST(TestPrimitiveBuilder, TestInit) {
   int n = 1000;
   ASSERT_OK(this->builder_->Reserve(n));
   ASSERT_EQ(util::next_power2(n), this->builder_->capacity());
-  ASSERT_EQ(util::next_power2(type_traits<Type>::bytes_required(n)),
+  ASSERT_EQ(util::next_power2(TypeTraits<Type>::bytes_required(n)),
       this->builder_->data()->size());
 
   // unsure if this should go in all builder classes
@@ -471,7 +471,7 @@ TYPED_TEST(TestPrimitiveBuilder, TestResize) {
   ASSERT_OK(this->builder_->Reserve(cap));
   ASSERT_EQ(cap, this->builder_->capacity());
 
-  ASSERT_EQ(type_traits<Type>::bytes_required(cap), this->builder_->data()->size());
+  ASSERT_EQ(TypeTraits<Type>::bytes_required(cap), this->builder_->data()->size());
   ASSERT_EQ(util::bytes_for_bits(cap), this->builder_->null_bitmap()->size());
 }
 

cpp/src/arrow/types/primitive.cc

@@ -87,7 +87,7 @@ Status PrimitiveBuilder<T>::Init(int32_t capacity) {
   RETURN_NOT_OK(ArrayBuilder::Init(capacity));
   data_ = std::make_shared<PoolBuffer>(pool_);
 
-  int64_t nbytes = type_traits<T>::bytes_required(capacity);
+  int64_t nbytes = TypeTraits<T>::bytes_required(capacity);
   RETURN_NOT_OK(data_->Resize(nbytes));
   // TODO(emkornfield) valgrind complains without this
   memset(data_->mutable_data(), 0, nbytes);
@@ -106,10 +106,9 @@ Status PrimitiveBuilder<T>::Resize(int32_t capacity) {
   } else {
     RETURN_NOT_OK(ArrayBuilder::Resize(capacity));
     const int64_t old_bytes = data_->size();
-    const int64_t new_bytes = type_traits<T>::bytes_required(capacity);
+    const int64_t new_bytes = TypeTraits<T>::bytes_required(capacity);
     RETURN_NOT_OK(data_->Resize(new_bytes));
     raw_data_ = reinterpret_cast<value_type*>(data_->mutable_data());
-
     memset(data_->mutable_data() + old_bytes, 0, new_bytes - old_bytes);
   }
   return Status::OK();
@@ -121,7 +120,7 @@ Status PrimitiveBuilder<T>::Append(
   RETURN_NOT_OK(Reserve(length));
 
   if (length > 0) {
-    memcpy(raw_data_ + length_, values, type_traits<T>::bytes_required(length));
+    memcpy(raw_data_ + length_, values, TypeTraits<T>::bytes_required(length));
   }
 
   // length_ is update by these
@@ -132,7 +131,12 @@ Status PrimitiveBuilder<T>::Append(
 
 template <typename T>
 Status PrimitiveBuilder<T>::Finish(std::shared_ptr<Array>* out) {
-  *out = std::make_shared<typename type_traits<T>::ArrayType>(
+  const int64_t bytes_required = TypeTraits<T>::bytes_required(length_);
+  if (bytes_required > 0 && bytes_required < data_->size()) {
+    // Trim buffers
+    RETURN_NOT_OK(data_->Resize(bytes_required));
+  }
+  *out = std::make_shared<typename TypeTraits<T>::ArrayType>(
       type_, length_, data_, null_count_, null_bitmap_);
 
   data_ = null_bitmap_ = nullptr;

cpp/src/arrow/types/primitive.h

@@ -184,77 +184,77 @@ class ARROW_EXPORT NumericBuilder : public PrimitiveBuilder<T> {
 };
 
 template <>
-struct type_traits<UInt8Type> {
+struct TypeTraits<UInt8Type> {
   typedef UInt8Array ArrayType;
 
   static inline int bytes_required(int elements) { return elements; }
 };
 
 template <>
-struct type_traits<Int8Type> {
+struct TypeTraits<Int8Type> {
   typedef Int8Array ArrayType;
 
   static inline int bytes_required(int elements) { return elements; }
 };
 
 template <>
-struct type_traits<UInt16Type> {
+struct TypeTraits<UInt16Type> {
   typedef UInt16Array ArrayType;
 
   static inline int bytes_required(int elements) { return elements * sizeof(uint16_t); }
 };
 
 template <>
-struct type_traits<Int16Type> {
+struct TypeTraits<Int16Type> {
   typedef Int16Array ArrayType;
 
   static inline int bytes_required(int elements) { return elements * sizeof(int16_t); }
 };
 
 template <>
-struct type_traits<UInt32Type> {
+struct TypeTraits<UInt32Type> {
   typedef UInt32Array ArrayType;
 
   static inline int bytes_required(int elements) { return elements * sizeof(uint32_t); }
 };
 
 template <>
-struct type_traits<Int32Type> {
+struct TypeTraits<Int32Type> {
   typedef Int32Array ArrayType;
 
   static inline int bytes_required(int elements) { return elements * sizeof(int32_t); }
 };
 
 template <>
-struct type_traits<UInt64Type> {
+struct TypeTraits<UInt64Type> {
   typedef UInt64Array ArrayType;
 
   static inline int bytes_required(int elements) { return elements * sizeof(uint64_t); }
 };
 
 template <>
-struct type_traits<Int64Type> {
+struct TypeTraits<Int64Type> {
   typedef Int64Array ArrayType;
 
   static inline int bytes_required(int elements) { return elements * sizeof(int64_t); }
 };
 
 template <>
-struct type_traits<TimestampType> {
+struct TypeTraits<TimestampType> {
   typedef TimestampArray ArrayType;
 
   static inline int bytes_required(int elements) { return elements * sizeof(int64_t); }
 };
 template <>
 
-struct type_traits<FloatType> {
+struct TypeTraits<FloatType> {
   typedef FloatArray ArrayType;
 
   static inline int bytes_required(int elements) { return elements * sizeof(float); }
 };
 
 template <>
-struct type_traits<DoubleType> {
+struct TypeTraits<DoubleType> {
   typedef DoubleArray ArrayType;
 
   static inline int bytes_required(int elements) { return elements * sizeof(double); }
@@ -294,7 +294,7 @@ class ARROW_EXPORT BooleanArray : public PrimitiveArray {
 };
 
 template <>
-struct type_traits<BooleanType> {
+struct TypeTraits<BooleanType> {
   typedef BooleanArray ArrayType;
 
   static inline int bytes_required(int elements) {

cpp/src/arrow/types/string-test.cc

@@ -66,18 +66,13 @@ class TestStringContainer : public ::testing::Test {
 
   void MakeArray() {
     length_ = offsets_.size() - 1;
-    int nchars = chars_.size();
-
     value_buf_ = test::to_buffer(chars_);
-    values_ = ArrayPtr(new UInt8Array(nchars, value_buf_));
-
     offsets_buf_ = test::to_buffer(offsets_);
-
     null_bitmap_ = test::bytes_to_null_buffer(valid_bytes_);
     null_count_ = test::null_count(valid_bytes_);
 
     strings_ = std::make_shared<StringArray>(
-        length_, offsets_buf_, values_, null_count_, null_bitmap_);
+        length_, offsets_buf_, value_buf_, null_count_, null_bitmap_);
   }
 
  protected:
@@ -94,7 +89,6 @@ class TestStringContainer : public ::testing::Test {
   int null_count_;
   int length_;
 
-  ArrayPtr values_;
   std::shared_ptr<StringArray> strings_;
 };
 
@@ -122,7 +116,7 @@ TEST_F(TestStringContainer, TestListFunctions) {
 
 TEST_F(TestStringContainer, TestDestructor) {
   auto arr = std::make_shared<StringArray>(
-      length_, offsets_buf_, values_, null_count_, null_bitmap_);
+      length_, offsets_buf_, value_buf_, null_count_, null_bitmap_);
 }
 
 TEST_F(TestStringContainer, TestGetString) {
@@ -221,18 +215,14 @@ class TestBinaryContainer : public ::testing::Test {
 
   void MakeArray() {
     length_ = offsets_.size() - 1;
-    int nchars = chars_.size();
-
     value_buf_ = test::to_buffer(chars_);
-    values_ = ArrayPtr(new UInt8Array(nchars, value_buf_));
-
     offsets_buf_ = test::to_buffer(offsets_);
 
     null_bitmap_ = test::bytes_to_null_buffer(valid_bytes_);
     null_count_ = test::null_count(valid_bytes_);
 
     strings_ = std::make_shared<BinaryArray>(
-        length_, offsets_buf_, values_, null_count_, null_bitmap_);
+        length_, offsets_buf_, value_buf_, null_count_, null_bitmap_);
   }
 
  protected:
@@ -249,7 +239,6 @@ class TestBinaryContainer : public ::testing::Test {
   int null_count_;
   int length_;
 
-  ArrayPtr values_;
   std::shared_ptr<BinaryArray> strings_;
 };
 
@@ -277,7 +266,7 @@ TEST_F(TestBinaryContainer, TestListFunctions) {
 
 TEST_F(TestBinaryContainer, TestDestructor) {
   auto arr = std::make_shared<BinaryArray>(
-      length_, offsets_buf_, values_, null_count_, null_bitmap_);
+      length_, offsets_buf_, value_buf_, null_count_, null_bitmap_);
 }
 
 TEST_F(TestBinaryContainer, TestGetValue) {

cpp/src/arrow/types/string.cc

@@ -39,7 +39,9 @@ BinaryArray::BinaryArray(const TypePtr& type, int32_t length,
       offset_buffer_(offsets),
       offsets_(reinterpret_cast<const int32_t*>(offset_buffer_->data())),
       data_buffer_(data),
-      data_(data_buffer_->data()) {}
+      data_(nullptr) {
+  if (data_buffer_ != nullptr) { data_ = data_buffer_->data(); }
+}
 
 Status BinaryArray::Validate() const {
   // TODO(wesm): what to do here?

cpp/src/arrow/types/string.h

@@ -58,8 +58,8 @@ class ARROW_EXPORT BinaryArray : public Array {
   }
 
   std::shared_ptr<Buffer> data() const { return data_buffer_; }
+  std::shared_ptr<Buffer> offsets() const { return offset_buffer_; }
 
-  const int32_t* offsets() const { return offsets_; }
   int32_t offset(int i) const { return offsets_[i]; }
 
   // Neither of these functions will perform boundschecking