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Diffstat (limited to 'vendor/google.golang.org/protobuf/reflect/protoreflect/value_unsafe.go')
-rw-r--r--vendor/google.golang.org/protobuf/reflect/protoreflect/value_unsafe.go98
1 files changed, 98 insertions, 0 deletions
diff --git a/vendor/google.golang.org/protobuf/reflect/protoreflect/value_unsafe.go b/vendor/google.golang.org/protobuf/reflect/protoreflect/value_unsafe.go
new file mode 100644
index 000000000..c45debdca
--- /dev/null
+++ b/vendor/google.golang.org/protobuf/reflect/protoreflect/value_unsafe.go
@@ -0,0 +1,98 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !purego,!appengine
+
+package protoreflect
+
+import (
+ "unsafe"
+
+ "google.golang.org/protobuf/internal/pragma"
+)
+
+type (
+ stringHeader struct {
+ Data unsafe.Pointer
+ Len int
+ }
+ sliceHeader struct {
+ Data unsafe.Pointer
+ Len int
+ Cap int
+ }
+ ifaceHeader struct {
+ Type unsafe.Pointer
+ Data unsafe.Pointer
+ }
+)
+
+var (
+ nilType = typeOf(nil)
+ boolType = typeOf(*new(bool))
+ int32Type = typeOf(*new(int32))
+ int64Type = typeOf(*new(int64))
+ uint32Type = typeOf(*new(uint32))
+ uint64Type = typeOf(*new(uint64))
+ float32Type = typeOf(*new(float32))
+ float64Type = typeOf(*new(float64))
+ stringType = typeOf(*new(string))
+ bytesType = typeOf(*new([]byte))
+ enumType = typeOf(*new(EnumNumber))
+)
+
+// typeOf returns a pointer to the Go type information.
+// The pointer is comparable and equal if and only if the types are identical.
+func typeOf(t interface{}) unsafe.Pointer {
+ return (*ifaceHeader)(unsafe.Pointer(&t)).Type
+}
+
+// value is a union where only one type can be represented at a time.
+// The struct is 24B large on 64-bit systems and requires the minimum storage
+// necessary to represent each possible type.
+//
+// The Go GC needs to be able to scan variables containing pointers.
+// As such, pointers and non-pointers cannot be intermixed.
+type value struct {
+ pragma.DoNotCompare // 0B
+
+ // typ stores the type of the value as a pointer to the Go type.
+ typ unsafe.Pointer // 8B
+
+ // ptr stores the data pointer for a String, Bytes, or interface value.
+ ptr unsafe.Pointer // 8B
+
+ // num stores a Bool, Int32, Int64, Uint32, Uint64, Float32, Float64, or
+ // Enum value as a raw uint64.
+ //
+ // It is also used to store the length of a String or Bytes value;
+ // the capacity is ignored.
+ num uint64 // 8B
+}
+
+func valueOfString(v string) Value {
+ p := (*stringHeader)(unsafe.Pointer(&v))
+ return Value{typ: stringType, ptr: p.Data, num: uint64(len(v))}
+}
+func valueOfBytes(v []byte) Value {
+ p := (*sliceHeader)(unsafe.Pointer(&v))
+ return Value{typ: bytesType, ptr: p.Data, num: uint64(len(v))}
+}
+func valueOfIface(v interface{}) Value {
+ p := (*ifaceHeader)(unsafe.Pointer(&v))
+ return Value{typ: p.Type, ptr: p.Data}
+}
+
+func (v Value) getString() (x string) {
+ *(*stringHeader)(unsafe.Pointer(&x)) = stringHeader{Data: v.ptr, Len: int(v.num)}
+ return x
+}
+func (v Value) getBytes() (x []byte) {
+ *(*sliceHeader)(unsafe.Pointer(&x)) = sliceHeader{Data: v.ptr, Len: int(v.num), Cap: int(v.num)}
+ return x
+}
+func (v Value) getIface() (x interface{}) {
+ *(*ifaceHeader)(unsafe.Pointer(&x)) = ifaceHeader{Type: v.typ, Data: v.ptr}
+ return x
+}