diff options
Diffstat (limited to 'src/util/share.h')
| -rw-r--r-- | src/util/share.h | 131 |
1 files changed, 48 insertions, 83 deletions
diff --git a/src/util/share.h b/src/util/share.h index 8f1e7045a..6e5a24d71 100644 --- a/src/util/share.h +++ b/src/util/share.h @@ -1,5 +1,6 @@ /* - * Inkscape::Util::ptr_shared<T> - like T const *, but stronger + * Inkscape::Util::ptr_shared<T> - like T const *, but stronger. + * Used to hold c-style strings for objects that are managed by the gc. * * Authors: * MenTaLguY <mental@rydia.net> @@ -19,120 +20,84 @@ namespace Inkscape { namespace Util { -template <typename T> class ptr_shared { public: - ptr_shared() : _obj(NULL) {} - template <typename T1> - ptr_shared(ptr_shared<T1> const &other) : _obj(other._obj) {} + ptr_shared() : _string(NULL) {} + ptr_shared(ptr_shared const &other) : _string(other._string) {} - T const *pointer() const { return _obj; } + operator char const *() const { return _string; } + operator bool() const { return _string; } - template <typename T1> - operator T1 const *() const { return _obj; } + char const *pointer() const { return _string; } + char const &operator[](int i) const { return _string[i]; } - operator bool() const { return _obj; } - - T const &operator*() const { return *_obj; } - T const *operator->() const { return _obj; } - T const &operator[](int i) const { return _obj[i]; } - - ptr_shared<T> operator+(int i) const { - return share_unsafe(_obj+i); + ptr_shared operator+(int i) const { + return share_unsafe(_string+i); } - ptr_shared<T> operator-(int i) const { - return share_unsafe(_obj-i); + ptr_shared operator-(int i) const { + return share_unsafe(_string-i); } - - ptr_shared<T> &operator+=(int i) const { - _obj += i; + //WARNING: No bounds checking in += and -= functions. Moving the pointer + //past the end of the string and then back could probably cause the garbage + //collector to deallocate the string inbetween, as there's temporary no + //valid reference pointing into the allocated space. + ptr_shared &operator+=(int i) { + _string += i; return *this; } - ptr_shared<T> &operator-=(int i) const { - _obj -= i; + ptr_shared &operator-=(int i) { + _string -= i; return *this; } - - template <typename T1> - std::ptrdiff_t operator-(ptr_shared<T1> const &other) { - return _obj - other._obj; + std::ptrdiff_t operator-(ptr_shared const &other) { + return _string - other._string; } - template <typename T1> - ptr_shared<T> &operator=(ptr_shared<T1> const &other) { - _obj = other._obj; + ptr_shared &operator=(ptr_shared const &other) { + _string = other._string; return *this; } - template <typename T1> - bool operator==(ptr_shared<T1> const &other) const { - return _obj == other._obj; + bool operator==(ptr_shared const &other) const { + return _string == other._string; } - - template <typename T1> - bool operator!=(ptr_shared<T1> const &other) const { - return _obj != other._obj; + bool operator!=(ptr_shared const &other) const { + return _string != other._string; } - - template <typename T1> - bool operator>(ptr_shared<T1> const &other) const { - return _obj > other._obj; + bool operator>(ptr_shared const &other) const { + return _string > other._string; } - - template <typename T1> - bool operator<(ptr_shared<T1> const &other) const { - return _obj < other._obj; - } - - static ptr_shared<T> share_unsafe(T const *obj) { - return ptr_shared<T>(obj); + bool operator<(ptr_shared const &other) const { + return _string < other._string; } -protected: - explicit ptr_shared(T const *obj) : _obj(obj) {} + friend ptr_shared share_unsafe(char const *string); private: - T const *_obj; -}; - -template <typename T> -inline ptr_shared<T> share(T const *obj) { - return share_unsafe(obj ? new T(*obj) : NULL); -} + ptr_shared(char const *string) : _string(string) {} + static ptr_shared share_unsafe(char const *string) { + return ptr_shared(string); + } -ptr_shared<char> share_string(char const *string); -ptr_shared<char> share_string(char const *string, std::size_t length); + //This class (and code usign it) assumes that it never has to free this + //pointer, and that the memory it points to will not be freed as long as a + //ptr_shared pointing to it exists. + char const *_string; +}; -template <typename T> -inline ptr_shared<T> reshare(T const *obj) { - return ptr_shared<T>::share_unsafe(obj); -} +ptr_shared share_string(char const *string); +ptr_shared share_string(char const *string, std::size_t length); -template <typename T> -inline ptr_shared<T> share_unsafe(T const *obj) { - return ptr_shared<T>::share_unsafe(obj); +inline ptr_shared share_unsafe(char const *string) { + return ptr_shared::share_unsafe(string); } -inline ptr_shared<char> share_static_string(char const *string) { +//TODO: Do we need this function? +inline ptr_shared share_static_string(char const *string) { return share_unsafe(string); } -template <typename T1, typename T2> -inline ptr_shared<T1> static_cast_shared(ptr_shared<T2> const &ref) { - return reshare(static_cast<T1 const *>(ref.pointer())); -} - -template <typename T1, typename T2> -inline ptr_shared<T1> dynamic_cast_shared(ptr_shared<T2> const &ref) { - return reshare(dynamic_cast<T1 const *>(ref.pointer())); -} - -template <typename T1, typename T2> -inline ptr_shared<T1> reinterpret_cast_shared(ptr_shared<T2> const &ref) { - return reshare(reinterpret_cast<T1 const *>(ref.pointer())); -} - } } |
