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@samdmarshall
Created June 7, 2014 20:27
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class DataBuffer {
var internalData: NSData;
init(fromData: NSData) {
self.internalData = NSData.dataWithData(fromData) as NSData;
}
init(fromFilePath: String) {
self.internalData = NSData.dataWithContentsOfFile(fromFilePath, options: .DataReadingMappedIfSafe, error: nil) as NSData;
}
// subscripting syntax to access raw pointer to bytes from offset ORIGIN
// e.g.: var pointer = myData[<offset from origin>]
subscript(origin: Int) -> UnsafePointer<UInt8> {
get {
var result: UnsafePointer<UInt8> = nil;
var dataLength = self.internalData.length();
if (origin < dataLength) {
var newLength = dataLength - origin;
var tempData = self.internalData.subdataWithRange(NSMakeRange(origin, newLength));
result = UnsafePointer<UInt8>(tempData.bytes());
}
return result;
}
}
// subscripting syntax to access SIZE number of bytes from offset ORIGIN
// e.g.: var value = myData[<offset from origin>, <number of bytes>]
subscript(origin: Int, size: Int) -> CChar[] {
get {
var result: CChar[] = [];
var dataLength = self.internalData.length();
if (origin < dataLength) {
var tempData = self.internalData.subdataWithRange(NSMakeRange(origin, size));
for index in 0...(tempData.length()-1) {
var byte = UnsafePointer<CChar>(tempData.bytes())[index];
result.append(byte);
}
}
return result;
}
}
}
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