The Tor Browser: comparison ipc/chromium/src/base/scoped

--1:000000000000
+:419c4751ce87
+// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+// Scopers help you manage ownership of a pointer, helping you easily manage the
+// a pointer within a scope, and automatically destroying the pointer at the
+// end of a scope.  There are two main classes you will use, which coorespond
+// to the operators new/delete and new[]/delete[].
+//
+// Example usage (scoped_ptr):
+//   {
+//     scoped_ptr<Foo> foo(new Foo("wee"));
+//   }  // foo goes out of scope, releasing the pointer with it.
+//
+//   {
+//     scoped_ptr<Foo> foo;          // No pointer managed.
+//     foo.reset(new Foo("wee"));    // Now a pointer is managed.
+//     foo.reset(new Foo("wee2"));   // Foo("wee") was destroyed.
+//     foo.reset(new Foo("wee3"));   // Foo("wee2") was destroyed.
+//     foo->Method();                // Foo::Method() called.
+//     foo.get()->Method();          // Foo::Method() called.
+//     SomeFunc(foo.Release());      // SomeFunc takes owernship, foo no longer
+//                                   // manages a pointer.
+//     foo.reset(new Foo("wee4"));   // foo manages a pointer again.
+//     foo.reset();                  // Foo("wee4") destroyed, foo no longer
+//                                   // manages a pointer.
+//   }  // foo wasn't managing a pointer, so nothing was destroyed.
+//
+// Example usage (scoped_array):
+//   {
+//     scoped_array<Foo> foo(new Foo[100]);
+//     foo.get()->Method();  // Foo::Method on the 0th element.
+//     foo[10].Method();     // Foo::Method on the 10th element.
+//   }
+#ifndef BASE_SCOPED_PTR_H_
+#define BASE_SCOPED_PTR_H_
+// This is an implementation designed to match the anticipated future TR2
+// implementation of the scoped_ptr class, and its closely-related brethren,
+// scoped_array, scoped_ptr_malloc.
+#include <assert.h>
+#include <stdlib.h>
+#include <cstddef>
+// A scoped_ptr<T> is like a T*, except that the destructor of scoped_ptr<T>
+// automatically deletes the pointer it holds (if any).
+// That is, scoped_ptr<T> owns the T object that it points to.
+// Like a T*, a scoped_ptr<T> may hold either NULL or a pointer to a T object.
+// Also like T*, scoped_ptr<T> is thread-compatible, and once you
+// dereference it, you get the threadsafety guarantees of T.
+//
+// The size of a scoped_ptr is small:
+// sizeof(scoped_ptr<C>) == sizeof(C*)
+template <class C>
+class scoped_ptr {
+public:
+// The element type
+typedef C element_type;
+// Constructor.  Defaults to intializing with NULL.
+// There is no way to create an uninitialized scoped_ptr.
+// The input parameter must be allocated with new.
+explicit scoped_ptr(C* p = NULL) : ptr_(p) { }
+// Destructor.  If there is a C object, delete it.
+// We don't need to test ptr_ == NULL because C++ does that for us.
+~scoped_ptr() {
+enum { type_must_be_complete = sizeof(C) };
+delete ptr_;
+}
+// Reset.  Deletes the current owned object, if any.
+// Then takes ownership of a new object, if given.
+// this->reset(this->get()) works.
+void reset(C* p = NULL) {
+if (p != ptr_) {
+enum { type_must_be_complete = sizeof(C) };
+delete ptr_;
+ptr_ = p;
+}
+}
+// Accessors to get the owned object.
+// operator* and operator-> will assert() if there is no current object.
+C& operator*() const {
+assert(ptr_ != NULL);
+return *ptr_;
+}
+C* operator->() const  {
+assert(ptr_ != NULL);
+return ptr_;
+}
+C* get() const { return ptr_; }
+// Comparison operators.
+// These return whether two scoped_ptr refer to the same object, not just to
+// two different but equal objects.
+bool operator==(C* p) const { return ptr_ == p; }
+bool operator!=(C* p) const { return ptr_ != p; }
+// Swap two scoped pointers.
+void swap(scoped_ptr& p2) {
+C* tmp = ptr_;
+ptr_ = p2.ptr_;
+p2.ptr_ = tmp;
+}
+// Release a pointer.
+// The return value is the current pointer held by this object.
+// If this object holds a NULL pointer, the return value is NULL.
+// After this operation, this object will hold a NULL pointer,
+// and will not own the object any more.
+C* release() {
+C* retVal = ptr_;
+ptr_ = NULL;
+return retVal;
+}
+private:
+C* ptr_;
+// Forbid comparison of scoped_ptr types.  If C2 != C, it totally doesn't
+// make sense, and if C2 == C, it still doesn't make sense because you should
+// never have the same object owned by two different scoped_ptrs.
+template <class C2> bool operator==(scoped_ptr<C2> const& p2) const;
+template <class C2> bool operator!=(scoped_ptr<C2> const& p2) const;
+// Disallow evil constructors
+scoped_ptr(const scoped_ptr&);
+void operator=(const scoped_ptr&);
+};
+// Free functions
+template <class C>
+void swap(scoped_ptr<C>& p1, scoped_ptr<C>& p2) {
+p1.swap(p2);
+}
+template <class C>
+bool operator==(C* p1, const scoped_ptr<C>& p2) {
+return p1 == p2.get();
+}
+template <class C>
+bool operator!=(C* p1, const scoped_ptr<C>& p2) {
+return p1 != p2.get();
+}
+// scoped_array<C> is like scoped_ptr<C>, except that the caller must allocate
+// with new [] and the destructor deletes objects with delete [].
+//
+// As with scoped_ptr<C>, a scoped_array<C> either points to an object
+// or is NULL.  A scoped_array<C> owns the object that it points to.
+// scoped_array<T> is thread-compatible, and once you index into it,
+// the returned objects have only the threadsafety guarantees of T.
+//
+// Size: sizeof(scoped_array<C>) == sizeof(C*)
+template <class C>
+class scoped_array {
+public:
+// The element type
+typedef C element_type;
+// Constructor.  Defaults to intializing with NULL.
+// There is no way to create an uninitialized scoped_array.
+// The input parameter must be allocated with new [].
+explicit scoped_array(C* p = NULL) : array_(p) { }
+// Destructor.  If there is a C object, delete it.
+// We don't need to test ptr_ == NULL because C++ does that for us.
+~scoped_array() {
+enum { type_must_be_complete = sizeof(C) };
+delete[] array_;
+}
+// Reset.  Deletes the current owned object, if any.
+// Then takes ownership of a new object, if given.
+// this->reset(this->get()) works.
+void reset(C* p = NULL) {
+if (p != array_) {
+enum { type_must_be_complete = sizeof(C) };
+delete[] array_;
+array_ = p;
+}
+}
+// Get one element of the current object.
+// Will assert() if there is no current object, or index i is negative.
+C& operator[](std::ptrdiff_t i) const {
+assert(i >= 0);
+assert(array_ != NULL);
+return array_[i];
+}
+// Get a pointer to the zeroth element of the current object.
+// If there is no current object, return NULL.
+C* get() const {
+return array_;
+}
+// Comparison operators.
+// These return whether two scoped_array refer to the same object, not just to
+// two different but equal objects.
+bool operator==(C* p) const { return array_ == p; }
+bool operator!=(C* p) const { return array_ != p; }
+// Swap two scoped arrays.
+void swap(scoped_array& p2) {
+C* tmp = array_;
+array_ = p2.array_;
+p2.array_ = tmp;
+}
+// Release an array.
+// The return value is the current pointer held by this object.
+// If this object holds a NULL pointer, the return value is NULL.
+// After this operation, this object will hold a NULL pointer,
+// and will not own the object any more.
+C* release() {
+C* retVal = array_;
+array_ = NULL;
+return retVal;
+}
+private:
+C* array_;
+// Forbid comparison of different scoped_array types.
+template <class C2> bool operator==(scoped_array<C2> const& p2) const;
+template <class C2> bool operator!=(scoped_array<C2> const& p2) const;
+// Disallow evil constructors
+scoped_array(const scoped_array&);
+void operator=(const scoped_array&);
+};
+// Free functions
+template <class C>
+void swap(scoped_array<C>& p1, scoped_array<C>& p2) {
+p1.swap(p2);
+}
+template <class C>
+bool operator==(C* p1, const scoped_array<C>& p2) {
+return p1 == p2.get();
+}
+template <class C>
+bool operator!=(C* p1, const scoped_array<C>& p2) {
+return p1 != p2.get();
+}
+// This class wraps the c library function free() in a class that can be
+// passed as a template argument to scoped_ptr_malloc below.
+class ScopedPtrMallocFree {
+public:
+inline void operator()(void* x) const {
+free(x);
+}
+};
+// scoped_ptr_malloc<> is similar to scoped_ptr<>, but it accepts a
+// second template argument, the functor used to free the object.
+template<class C, class FreeProc = ScopedPtrMallocFree>
+class scoped_ptr_malloc {
+public:
+// The element type
+typedef C element_type;
+// Constructor.  Defaults to intializing with NULL.
+// There is no way to create an uninitialized scoped_ptr.
+// The input parameter must be allocated with an allocator that matches the
+// Free functor.  For the default Free functor, this is malloc, calloc, or
+// realloc.
+explicit scoped_ptr_malloc(C* p = NULL): ptr_(p) {}
+// Destructor.  If there is a C object, call the Free functor.
+~scoped_ptr_malloc() {
+free_(ptr_);
+}
+// Reset.  Calls the Free functor on the current owned object, if any.
+// Then takes ownership of a new object, if given.
+// this->reset(this->get()) works.
+void reset(C* p = NULL) {
+if (ptr_ != p) {
+free_(ptr_);
+ptr_ = p;
+}
+}
+// Get the current object.
+// operator* and operator-> will cause an assert() failure if there is
+// no current object.
+C& operator*() const {
+assert(ptr_ != NULL);
+return *ptr_;
+}
+C* operator->() const {
+assert(ptr_ != NULL);
+return ptr_;
+}
+C* get() const {
+return ptr_;
+}
+// Comparison operators.
+// These return whether a scoped_ptr_malloc and a plain pointer refer
+// to the same object, not just to two different but equal objects.
+// For compatibility wwith the boost-derived implementation, these
+// take non-const arguments.
+bool operator==(C* p) const {
+return ptr_ == p;
+}
+bool operator!=(C* p) const {
+return ptr_ != p;
+}
+// Swap two scoped pointers.
+void swap(scoped_ptr_malloc & b) {
+C* tmp = b.ptr_;
+b.ptr_ = ptr_;
+ptr_ = tmp;
+}
+// Release a pointer.
+// The return value is the current pointer held by this object.
+// If this object holds a NULL pointer, the return value is NULL.
+// After this operation, this object will hold a NULL pointer,
+// and will not own the object any more.
+C* release() {
+C* tmp = ptr_;
+ptr_ = NULL;
+return tmp;
+}
+private:
+C* ptr_;
+// no reason to use these: each scoped_ptr_malloc should have its own object
+template <class C2, class GP>
+bool operator==(scoped_ptr_malloc<C2, GP> const& p) const;
+template <class C2, class GP>
+bool operator!=(scoped_ptr_malloc<C2, GP> const& p) const;
+static FreeProc const free_;
+// Disallow evil constructors
+scoped_ptr_malloc(const scoped_ptr_malloc&);
+void operator=(const scoped_ptr_malloc&);
+};
+template<class C, class FP>
+FP const scoped_ptr_malloc<C, FP>::free_ = FP();
+template<class C, class FP> inline
+void swap(scoped_ptr_malloc<C, FP>& a, scoped_ptr_malloc<C, FP>& b) {
+a.swap(b);
+}
+template<class C, class FP> inline
+bool operator==(C* p, const scoped_ptr_malloc<C, FP>& b) {
+return p == b.get();
+}
+template<class C, class FP> inline
+bool operator!=(C* p, const scoped_ptr_malloc<C, FP>& b) {
+return p != b.get();
+}
+#endif  // BASE_SCOPED_PTR_H_

The Tor Browser / file comparison

comparison: ipc/chromium/src/base/scoped_ptr.h

ipc/chromium/src/base/scoped_ptr.h