llvm-6502/include/llvm/ADT/OwningPtr.h
2008-12-08 17:28:11 +00:00

135 lines
3.4 KiB
C++

//===- llvm/ADT/OwningPtr.h - Smart ptr that owns the pointee ---*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines and implements the OwningPtr class.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_ADT_OWNING_PTR_H
#define LLVM_ADT_OWNING_PTR_H
#include <cassert>
#include <cstddef>
namespace llvm {
/// OwningPtr smart pointer - OwningPtr mimics a built-in pointer except that it
/// guarantees deletion of the object pointed to, either on destruction of the
/// OwningPtr or via an explicit reset(). Once created, ownership of the
/// pointee object can be taken away from OwningPtr by using the take method.
template<class T>
class OwningPtr {
OwningPtr(OwningPtr const &); // DO NOT IMPLEMENT
OwningPtr &operator=(OwningPtr const &); // DO NOT IMPLEMENT
T *Ptr;
public:
explicit OwningPtr(T *P = 0) : Ptr(P) {}
~OwningPtr() {
delete Ptr;
}
/// reset - Change the current pointee to the specified pointer. Note that
/// calling this with any pointer (including a null pointer) deletes the
/// current pointer.
void reset(T *P = 0) {
if (P == Ptr) return;
T *Tmp = Ptr;
Ptr = P;
delete Tmp;
}
/// take - Reset the owning pointer to null and return its pointer. This does
/// not delete the pointer before returning it.
T *take() {
T *Tmp = Ptr;
Ptr = 0;
return Tmp;
}
T &operator*() const {
assert(Ptr && "Cannot dereference null pointer");
return *Ptr;
}
T *operator->() const { return Ptr; }
T *get() const { return Ptr; }
operator bool() const { return Ptr != 0; }
bool operator!() const { return Ptr == 0; }
void swap(OwningPtr &RHS) {
T *Tmp = RHS.Ptr;
RHS.Ptr = Ptr;
Ptr = Tmp;
}
};
template<class T>
inline void swap(OwningPtr<T> &a, OwningPtr<T> &b) {
a.swap(b);
}
/// OwningArrayPtr smart pointer - OwningArrayPtr provides the same
/// functionality as OwningPtr, except that it works for array types.
template<class T>
class OwningArrayPtr {
OwningArrayPtr(OwningArrayPtr const &); // DO NOT IMPLEMENT
OwningArrayPtr &operator=(OwningArrayPtr const &); // DO NOT IMPLEMENT
T *Ptr;
public:
explicit OwningArrayPtr(T *P = 0) : Ptr(P) {}
~OwningArrayPtr() {
delete [] Ptr;
}
/// reset - Change the current pointee to the specified pointer. Note that
/// calling this with any pointer (including a null pointer) deletes the
/// current pointer.
void reset(T *P = 0) {
if (P == Ptr) return;
T *Tmp = Ptr;
Ptr = P;
delete [] Tmp;
}
/// take - Reset the owning pointer to null and return its pointer. This does
/// not delete the pointer before returning it.
T *take() {
T *Tmp = Ptr;
Ptr = 0;
return Tmp;
}
T &operator[](std::ptrdiff_t i) const {
assert(Ptr && "Cannot dereference null pointer");
return Ptr[i];
}
T *get() const { return Ptr; }
operator bool() const { return Ptr != 0; }
bool operator!() const { return Ptr == 0; }
void swap(OwningArrayPtr &RHS) {
T *Tmp = RHS.Ptr;
RHS.Ptr = Ptr;
Ptr = Tmp;
}
};
template<class T>
inline void swap(OwningArrayPtr<T> &a, OwningArrayPtr<T> &b) {
a.swap(b);
}
} // end namespace llvm
#endif