MemoryBuffer
private let emptyMemory = malloc(1)!
class MemoryBuffer:Equatable,CustomStringConvertible
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public internal(set) var memory: UnsafeMutableRawPointer
var capacity: Int
public internal(set) var length: Int
var freeWhenDone: Bool
public init(copyOf buffer: MemoryBuffer) {
// malloc
self.memory = malloc(buffer.length)
// copy
memcpy(self.memory, buffer.memory, buffer.length)
self.capacity = buffer.length
self.length = buffer.length
// default free when down
self.freeWhenDone = true
}
public init(memory: UnsafeMutableRawPointer, capacity: Int, length: Int, freeWhenDone: Bool) {
self.memory = memory
self.capacity = capacity
self.length = length
self.freeWhenDone = freeWhenDone
}
public init(data: Data) {
if data.count == 0 {
self.memory = emptyMemory
self.capacity = 0
self.length = 0
self.freeWhenDone = false
} else {
// malloc
self.memory = malloc(data.count)!
// copy [data copyBytesTo:count:]
data.copyBytes(to: self.memory.assumingMemoryBound(to: UInt8.self), count: data.count)
self.capacity = data.count
self.length = data.count
self.freeWhenDone = true
}
}
public init() {
// empty memory with 1 byte
self.memory = emptyMemory
self.capacity = 0
self.length = 0
self.freeWhenDone = false
}
// make data
public func makeData() -> Data {
if self.length == 0 {
return Data()
} else {
// [Data initBytes:count:]
return Data(bytes: self.memory, count: self.length)
}
}
// description
public var description: String {
let hexString = NSMutableString()
let bytes = self.memory.assumingMemoryBound(to: UInt8.self)
for i in 0 ..< self.length {
// dump every byte in hex representation
hexString.appendFormat("%02x", UInt(bytes[i]))
}
return hexString as String
}