github.com/sagernet/gvisor@v0.0.0-20240428053021-e691de28565f/pkg/bits/bits.go (about)

     1  // Copyright 2018 The gVisor Authors.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  // Package bits includes all bit related types and operations.
    16  package bits
    17  
    18  // AlignUp rounds a length up to an alignment. align must be a power of 2.
    19  func AlignUp(length int, align uint) int {
    20  	return (length + int(align) - 1) & ^(int(align) - 1)
    21  }
    22  
    23  // AlignDown rounds a length down to an alignment. align must be a power of 2.
    24  func AlignDown(length int, align uint) int {
    25  	return length & ^(int(align) - 1)
    26  }