# QCA::MemoryRegion Class Reference
[QCA user API]

Array of bytes that may be optionally secured. More...

`#include <QtCrypto>`

Inheritance diagram for QCA::MemoryRegion:

Collaboration diagram for QCA::MemoryRegion:

[legend]

List of all members.

## Public Member Functions

const char & | at (int index) const
const char * | constData () const
const char * | data () const
bool | isEmpty () const
bool | isNull () const
bool | isSecure () const
| MemoryRegion (const MemoryRegion &from)
| MemoryRegion (const QByteArray &from)
| MemoryRegion (const char *str)
MemoryRegion & | operator= (const QByteArray &from)
MemoryRegion & | operator= (const MemoryRegion &from)
int | size () const
QByteArray | toByteArray () const

## Protected Member Functions

char & | at (int index)
char * | data ()
| MemoryRegion (const QByteArray &from, bool secure)
| MemoryRegion (int size, bool secure)
| MemoryRegion (bool secure)
bool | resize (int size)
void | set (const QByteArray &from, bool secure)
void | setSecure (bool secure)

## Detailed Description

Array of bytes that may be optionally secured.

This class is mostly unusable on its own. Either use it as a SecureArray subclass or call toByteArray() to convert to QByteArray.

Note that this class is implicitly shared (that is, copy on write).

Examples:

  aes-cmac.cpp.

## Constructor & Destructor Documentation

QCA::MemoryRegion::MemoryRegion | ( | const char * | str | ) |

Constructs a new Memory Region from a null terminated character array.

Parameters:

  | str | pointer to the array of data to copy

QCA::MemoryRegion::MemoryRegion | ( | const QByteArray & | from | ) |

Constructs a new MemoryRegion from the data in a byte array.

Parameters:

  | from | the QByteArray to copy from

QCA::MemoryRegion::MemoryRegion | ( | const MemoryRegion & | from | ) |

Standard copy constructor.

Parameters:

  | from | the MemoryRegion to copy from

QCA::MemoryRegion::MemoryRegion | ( | bool | secure | ) | `[protected]`

Create a memory region, optionally using secure storage.

Parameters:

  | secure | if this is true, the memory region will use secure storage.

Note:
  This will create a memory region without any content (i.e. both isNull() and isEmpty() will return true.

QCA::MemoryRegion::MemoryRegion | ( | int | size,
|  | bool | secure |
| ) |  |  | `[protected]`

Create a memory region, optionally using secure storage.

Parameters:

  | size | the number of bytes in the memory region.
  | secure | if this is true, the memory region will use secure storage.

QCA::MemoryRegion::MemoryRegion | ( | const QByteArray & | from,
|  | bool | secure |
| ) |  |  | `[protected]`

Create a memory region, optionally using secure storage.

This constructor variant allows you to initialize the memory region from an existing array.

Parameters:

  | from | the byte array to copy from.
  | secure | if this is true, the memory region will use secure storage.

## Member Function Documentation

char& QCA::MemoryRegion::at | ( | int | index | ) | `[protected]`

Obtain the value of the memory location at the specified position.

Parameters:

  | index | the offset into the memory region.

Note:
  The contents of a memory region are between 0 and size()-1. The content at position size() is always a null terminator.

Reimplemented in QCA::SecureArray.

const char& QCA::MemoryRegion::at | ( | int | index | ) | const

Obtain the value of the memory location at the specified position.

Parameters:

  | index | the offset into the memory region.

Note:
  The contents of a memory region are between 0 and size()-1. The content at position size() is always a null terminator.

Reimplemented in QCA::SecureArray.

const char* QCA::MemoryRegion::constData | ( |  | ) | const

Convert the contents of the memory region to a C-compatible character array.

This consists of size() bytes, followed by a null terminator.

See also:
  toByteArray for an alternative approach.

  data which is equivalent to this method

Reimplemented in QCA::SecureArray.

char* QCA::MemoryRegion::data | ( |  | ) | `[protected]`

Convert the contents of the memory region to a C-compatible character array.

This consists of size() bytes, followed by a null terminator.

Reimplemented in QCA::SecureArray.

const char* QCA::MemoryRegion::data | ( |  | ) | const

Convert the contents of the memory region to a C-compatible character array.

This consists of size() bytes, followed by a null terminator.

See also:
  toByteArray for an alternative approach.

  constData, which is equivalent to this method, but avoids the possibility that the compiler picks the wrong version.

Reimplemented in QCA::SecureArray.

bool QCA::MemoryRegion::isEmpty | ( |  | ) | const

Returns true if the size of the memory region is zero.

Reimplemented in QCA::SecureArray.

bool QCA::MemoryRegion::isNull | ( |  | ) | const

Test if the MemoryRegion is null (i.e.

was created as a null array, and hasn't been resized).

This is probably not what you are trying to do. If you are trying to determine whether there are any bytes in the array, use isEmpty() instead.

bool QCA::MemoryRegion::isSecure | ( |  | ) | const

Test if the MemoryRegion is using secure memory, or not.

In this context, memory is secure if it will not be paged out to disk.

Returns:
  true if the memory region is secure

MemoryRegion& QCA::MemoryRegion::operator= | ( | const QByteArray & | from | ) |

Standard assignment operator.

Parameters:

  | from | the QByteArray to copy from

Reimplemented in QCA::SecureArray.

MemoryRegion& QCA::MemoryRegion::operator= | ( | const MemoryRegion & | from | ) |

Standard assignment operator.

Parameters:

  | from | the MemoryRegion to copy from

bool QCA::MemoryRegion::resize | ( | int | size | ) | `[protected]`

Resize the memory region to the specified size.

Parameters:

  | size | the new size of the region.

Reimplemented in QCA::SecureArray.

void QCA::MemoryRegion::set | ( | const QByteArray & | from,
|  | bool | secure |
| ) |  |  | `[protected]`

Modify the memory region to match a specified byte array.

This resizes the memory region as required to match the byte array size.

Parameters:

  | from | the byte array to copy from.
  | secure | if this is true, the memory region will use secure storage.

void QCA::MemoryRegion::setSecure | ( | bool | secure | ) | `[protected]`

Convert the memory region to use the specified memory type.

This may involve copying data from secure to insecure storage, or from insecure to secure storage.

Parameters:

  | secure | if true, use secure memory; otherwise use insecure memory.

int QCA::MemoryRegion::size | ( |  | ) | const

Returns the number of bytes in the memory region.

Reimplemented in QCA::SecureArray.

QByteArray QCA::MemoryRegion::toByteArray | ( |  | ) | const

Convert this memory region to a byte array.

Note:
  For secure data, this will make it insecure

See also:
  data() and constData() for other ways to convert to an "accessible" format.

Reimplemented in QCA::SecureArray.

The documentation for this class was generated from the following file:

- qca_tools.h