ios - 警告消息 : How do I remove 'withUnsafeMutableBytes' is deprecated and 'withUnsafeBytes' is deprecated?

Question

我正在将代码从以前版本的 Swift 更改为 Swift5。并且有一条警告消息表明此代码不可用。我想更改此代码，但不知道如何更改。

警告代码

 func pbkdf2(hash: CCPBKDFAlgorithm, password: String, salt: Data, keyByteCount: Int, round: Int) -> Data? {
        let passwordData = password.data(using: .utf8)!
        let derivedKeyData = Data(count: keyByteCount)
        var localVariables = derivedKeyData
        let derivationStatus = localVariables.withUnsafeMutableBytes { derivedKeyBytes  in
            salt.withUnsafeBytes { saltBytes in
                CCKeyDerivationPBKDF(CCPBKDFAlgorithm(kCCPBKDF2),
                                     password, passwordData.count, saltBytes, salt.count,
                                     hash, UInt32(round),
                                     derivedKeyBytes, derivedKeyData.count)
            }
        }

        if (derivationStatus != 0) {
            Log.Error("\(derivationStatus)")
            return nil;
        }

        return localVariables
    }

警告消息:

'withUnsafeMutableBytes' is deprecated: use withUnsafeMutableBytes<R>(_: (UnsafeMutableRawBufferPointer) throws
-> R) rethrows -> R instead

'withUnsafeBytes' is deprecated: use withUnsafeBytes<R>(_: (UnsafeRawBufferPointer) throws -> R) rethrows
-> R instead

如何更改此代码以删除警告消息？

我尝试了很多方法，但错误发生了变化。

func pbkdf2(hash: CCPBKDFAlgorithm, password: String, salt: Data, keyByteCount: Int, round: Int) -> Data? {
  let passwordData = password.data(using: .utf8)!
  let derivedKeyData = Data(count: keyByteCount)
  var localVariables = derivedKeyData
  let derivationStatus = localVariables.withUnsafeMutableBytes { derivedKeyBytes  in
     let Mutable: UnsafeMutableRawPointer? = derivedKeyBytes.baseAddress
     salt.withUnsafeBytes { saltBytes in
           let raw: UnsafeRawPointer? = saltBytes.baseAddress
              CCKeyDerivationPBKDF(CCPBKDFAlgorithm(kCCPBKDF2),
                                     password, passwordData.count, raw?.assumingMemoryBound(to: UInt8.self), salt.count,
                                     hash, UInt32(round),
                                     Mutable?.assumingMemoryBound(to: UInt8.self) , derivedKeyData.count)
            }
        }

        if (derivationStatus != 0) {
            Log.Error("\(derivationStatus)")
            return nil;
        }

        return localVariables
    }

错误信息:

Binary operator '!=' cannot be applied to operands of type '()' and 'Int'

警告消息:

Constant 'derivationStatus' inferred to have type '()', which may be unexpected

我改变它正确吗？我想我需要纠正比较，我应该如何纠正它？

Answer 1

我在@MartinR的帮助下解决了这个问题。 This is the link @MartinR 建议作为答案。

将 saltBytes 替换为 saltBytes.bindMemory(to: UInt8.self).baseAddress，对于 衍生 key 字节 也类似。

成功的代码，但缺少所有警告

func pbkdf2(hash: CCPBKDFAlgorithm, password: String, salt: Data, keyByteCount: Int, round: Int) -> Data? {
    let passwordData = password.data(using: .utf8)!
    let derivedKeyData = Data(count: keyByteCount)
    var localVariables = derivedKeyData
    let derivationStatus = localVariables.withUnsafeMutableBytes { derivedKeyBytes  in
      salt.withUnsafeBytes { saltBytes in

       CCKeyDerivationPBKDF(CCPBKDFAlgorithm(kCCPBKDF2),
                          password, passwordData.count, saltBytes.bindMemory(to: UInt8.self).baseAddress, salt.count,
                          hash, UInt32(round),
                          derivedKeyBytes.bindMemory(to: UInt8.self).baseAddress , derivedKeyData.count)
            }
        }

        if (derivationStatus != 0) {
                 Log.Error("\(derivationStatus)")
                 return nil;
        }

        return localVariables
    }