import quincy 17.2.0

[ceph.git] / ceph / src / arrow / go / arrow / type_traits_decimal128.go

diff --git a/ceph/src/arrow/go/arrow/type_traits_decimal128.go b/ceph/src/arrow/go/arrow/type_traits_decimal128.go
new file mode 100644 (file)
index 0000000..ee8eb00
--- /dev/null
+++ b/ceph/src/arrow/go/arrow/type_traits_decimal128.go
@@ -0,0 +1,75 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package arrow
+
+import (
+       "reflect"
+       "unsafe"
+
+       "github.com/apache/arrow/go/v6/arrow/decimal128"
+       "github.com/apache/arrow/go/v6/arrow/endian"
+)
+
+// Decimal128 traits
+var Decimal128Traits decimal128Traits
+
+const (
+       // Decimal128SizeBytes specifies the number of bytes required to store a single decimal128 in memory
+       Decimal128SizeBytes = int(unsafe.Sizeof(decimal128.Num{}))
+)
+
+type decimal128Traits struct{}
+
+// BytesRequired returns the number of bytes required to store n elements in memory.
+func (decimal128Traits) BytesRequired(n int) int { return Decimal128SizeBytes * n }
+
+// PutValue
+func (decimal128Traits) PutValue(b []byte, v decimal128.Num) {
+       endian.Native.PutUint64(b[:8], uint64(v.LowBits()))
+       endian.Native.PutUint64(b[8:], uint64(v.HighBits()))
+}
+
+// CastFromBytes reinterprets the slice b to a slice of type uint16.
+//
+// NOTE: len(b) must be a multiple of Uint16SizeBytes.
+func (decimal128Traits) CastFromBytes(b []byte) []decimal128.Num {
+       h := (*reflect.SliceHeader)(unsafe.Pointer(&b))
+
+       var res []decimal128.Num
+       s := (*reflect.SliceHeader)(unsafe.Pointer(&res))
+       s.Data = h.Data
+       s.Len = h.Len / Decimal128SizeBytes
+       s.Cap = h.Cap / Decimal128SizeBytes
+
+       return res
+}
+
+// CastToBytes reinterprets the slice b to a slice of bytes.
+func (decimal128Traits) CastToBytes(b []decimal128.Num) []byte {
+       h := (*reflect.SliceHeader)(unsafe.Pointer(&b))
+
+       var res []byte
+       s := (*reflect.SliceHeader)(unsafe.Pointer(&res))
+       s.Data = h.Data
+       s.Len = h.Len * Decimal128SizeBytes
+       s.Cap = h.Cap * Decimal128SizeBytes
+
+       return res
+}
+
+// Copy copies src to dst.
+func (decimal128Traits) Copy(dst, src []decimal128.Num) { copy(dst, src) }