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/**
* HiddenPointer.h
*
* Helper class that we use to hide a pointer in a string. We do this
* by creating a string buffer that is a littlebit bigger, and put
* the hidden pointer in front of the name
*
* @author Emiel Bruijntjes <emiel.bruijntjes@copernica.com>
* @copyright 2013 Copernica BV
*/
/**
* Set up namespace
*/
namespace Php {
/**
* Class definition
*/
template <typename Type>
class HiddenPointer
{
public:
/**
* Constructor to hide the pointer in a buffer
* @param pointer The pointer to hide
* @param text The visible text
* @param size Optional text size
*/
HiddenPointer(Type *pointer, const char *text, int size=-1)
{
// calculate size
if (size < 0) size = strlen(text);
// reserve enough room for the text and the pointer
_data.reserve(size + sizeof(Type *));
// store the pointer
_data.assign(std::string((const char *)&pointer, sizeof(Type *)));
// append the text
_data.append(text, size);
// store pointers
_pointer = pointer;
_text = _data.c_str() + sizeof(Type *);
}
/**
* Hide pointer in buffer
* @param pointer
* @param text
*/
HiddenPointer(Type *pointer, const std::string &text) : HiddenPointer(pointer, text.c_str(), text.size()) {}
/**
* Constructor to retrieve the object given a buffer
* @param text The visible text
* @param size Size of the text
*/
HiddenPointer(const char *text, int size=-1)
{
// calculate size
if (size < 0) size = strlen(text);
// the pointer is stored right in front of the name
_pointer = *((Type **)(text - sizeof(Type *)));
_text = text;
}
/**
* Copy constructor
* @param that
*/
HiddenPointer(const HiddenPointer<Type> &that) : _pointer(that._pointer), _text(that._text), _data(that._data)
{
// if data is filled, the text is located inside the data
if (_data.size() > 0) _text = _data.c_str() + sizeof(Type *);
}
/**
* Destructor
*/
virtual ~HiddenPointer() {}
/**
* Assignment operator
* @param that
* @return HiddenPointer
*/
HiddenPointer<Type> operator=(const HiddenPointer &that)
{
// skip self assignment
if (&that == this) return *this;
// copy members
_pointer = that._pointer;
_text = that._text;
_data = that._data;
// if data is filled, the text is located inside the data
if (_data.size() > 0) _text = _data.c_str() + sizeof(Type *);
}
/**
* Retrieve the pointer
* @return Type*
*/
Type *pointer() const
{
return _pointer;
}
/**
* Change the pointer
* @param Type*
*/
void setPointer(Type *pointer)
{
// store pointer
_pointer = pointer;
// overwrite in data
_data.replace(0, sizeof(Type *), (const char *)&_pointer, sizeof(Type *));
// for safety reasons, we recalculate text pointer
_text = _data.c_str() + sizeof(Type *);
}
/**
* Retrieve the text
* @return const char *
*/
const char *text() const
{
return _text;
}
/**
* Change the text
* @param text
* @param size
*/
void setText(const char *text, int size=-1)
{
// check if size was set
if (size < 0) size = strlen(text);
// reserve enough room for the text and the pointer
_data.reserve(size + sizeof(Type *));
// store the pointer
_data.assign(std::string((const char *)&_pointer, sizeof(Type *)));
// append the text
_data.append(text, size);
// store new text
_text = _data.c_str() + sizeof(Type *);
}
/**
* Cast to the pointer
* @return Type*
*/
operator Type* () const
{
return _pointer;
}
/**
* Cast to text
* @return const char *
*/
operator const char * () const
{
return _text;
}
/**
* Length of the text
* @return int
*/
int length() const
{
return _data.size() - sizeof(Type *);
}
private:
/**
* The actual pointer
* @var Type*
*/
Type *_pointer;
/**
* The original text
* @var text
*/
const char *_text;
/**
* Optional data buffer
* @var string
*/
std::string _data;
};
/**
* End of namespace
*/
}
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