diff options
Diffstat (limited to 'pkg/sentry/arch/aligned.go')
-rw-r--r-- | pkg/sentry/arch/aligned.go | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/pkg/sentry/arch/aligned.go b/pkg/sentry/arch/aligned.go new file mode 100644 index 000000000..df01a903d --- /dev/null +++ b/pkg/sentry/arch/aligned.go @@ -0,0 +1,31 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed 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 arch + +import ( + "reflect" +) + +// alignedBytes returns a slice of size bytes, aligned in memory to the given +// alignment. This is used because we require certain structures to be aligned +// in a specific way (for example, the X86 floating point data). +func alignedBytes(size, alignment uint) []byte { + data := make([]byte, size+alignment-1) + offset := uint(reflect.ValueOf(data).Index(0).Addr().Pointer() % uintptr(alignment)) + if offset == 0 { + return data[:size:size] + } + return data[alignment-offset:][:size:size] +} |