Cast for argument to delete[] - VC6 doesn't want to delete a const pointer

[wxWidgets.git] / include / wx / vector.h

diff --git a/include/wx/vector.h b/include/wx/vector.h
index e3792543e6570d3a4dbf714da1c0698ab57d30a1..85d925794371ef7e0b162d2def26a4ce7eaf8823 100644 (file)
--- a/include/wx/vector.h
+++ b/include/wx/vector.h
@@ -21,20 +21,112 @@
 
 #else // !wxUSE_STL
 
 
 #else // !wxUSE_STL
 

+#include "wx/utils.h"
+#include "wx/meta/movable.h"
+#include "wx/meta/if.h"
+
+#include "wx/beforestd.h"
+#include <new> // for placement new
+#include "wx/afterstd.h"
+
+namespace wxPrivate
+{
+
+// These templates encapsulate memory operations for use by wxVector; there are
+// two implementations, both in generic way for any C++ types and as an
+// optimized version for "movable" types that uses realloc() and memmove().
+
+// version for movable types:
+template<typename T>
+struct wxVectorMemOpsMovable
+{
+    static void Free(T* array)
+        { free(array); }
+
+    static T* Realloc(T* old, size_t newCapacity, size_t WXUNUSED(occupiedSize))
+        { return (T*)realloc(old, newCapacity * sizeof(T)); }
+
+    static void MemmoveBackward(T* dest, T* source, size_t count)
+        { memmove(dest, source, count * sizeof(T)); }
+
+    static void MemmoveForward(T* dest, T* source, size_t count)
+        { memmove(dest, source, count * sizeof(T)); }
+};
+
+// generic version for non-movable types:
+template<typename T>
+struct wxVectorMemOpsGeneric
+{
+    static void Free(T* array)
+        { ::operator delete(array); }
+
+    static T* Realloc(T* old, size_t newCapacity, size_t occupiedSize)
+    {
+        T *mem = (T*)::operator new(newCapacity * sizeof(T));
+        for ( size_t i = 0; i < occupiedSize; i++ )
+        {
+            new(mem + i) T(old[i]);
+            old[i].~T();
+        }
+        ::operator delete(old);
+        return mem;
+    }
+
+    static void MemmoveBackward(T* dest, T* source, size_t count)
+    {
+        wxASSERT( dest < source );
+        T* destptr = dest;
+        T* sourceptr = source;
+        for ( size_t i = count; i > 0; --i, ++destptr, ++sourceptr )
+        {
+            new(destptr) T(*sourceptr);
+            sourceptr->~T();
+        }
+    }
+
+    static void MemmoveForward(T* dest, T* source, size_t count)
+    {
+        wxASSERT( dest > source );
+        T* destptr = dest + count - 1;
+        T* sourceptr = source + count - 1;
+        for ( size_t i = count; i > 0; --i, --destptr, --sourceptr )
+        {
+            new(destptr) T(*sourceptr);
+            sourceptr->~T();
+        }
+    }
+};
+
+
+} // namespace wxPrivate
+

 template<typename T>
 class wxVector
 {
 template<typename T>
 class wxVector
 {

+private:
+    // This cryptic expression means "typedef Ops to wxVectorMemOpsMovable if
+    // type T is movable type, otherwise to wxVectorMemOpsGeneric".
+    //
+    // Note that we use typedef instead of privately deriving from this (which
+    // would allowed us to omit "Ops::" prefixes below) to keep VC6 happy,
+    // it can't compile code that derives from wxIf<...>::value.
+    typedef typename wxIf< wxIsMovable<T>::value,
+                           wxPrivate::wxVectorMemOpsMovable<T>,
+                           wxPrivate::wxVectorMemOpsGeneric<T> >::value
+            Ops;
+

 public:
     typedef size_t size_type;
     typedef T value_type;
     typedef value_type* iterator;
 public:
     typedef size_t size_type;
     typedef T value_type;
     typedef value_type* iterator;

+    typedef const value_type* const_iterator;

     typedef value_type& reference;
 
     typedef value_type& reference;
 

-    wxVector() : m_allocsize(16), m_size(0), m_capacity(0), m_objects(0) {}
+    wxVector() : m_size(0), m_capacity(0), m_values(NULL) {}

 
     wxVector(const wxVector& c)
     {
 
     wxVector(const wxVector& c)
     {

-        wxCHECK2(Copy(c), return);
+        Copy(c);

     }
 
     ~wxVector()
     }
 
     ~wxVector()


@@ -44,19 +136,35 @@ public:
 
     void clear()
     {
 
     void clear()
     {

-        for (size_type i = 0; i < size(); i++)
-            delete m_objects[i];
-        free(m_objects);
-        m_objects = 0;
+        // call destructors of stored objects:
+        for ( size_type i = 0; i < m_size; i++ )
+        {
+            m_values[i].~T();
+        }
+
+        Ops::Free(m_values);
+        m_values = NULL;

         m_size = m_capacity = 0;
     }
 
     void reserve(size_type n)
     {
         m_size = m_capacity = 0;
     }
 
     void reserve(size_type n)
     {

-        if ( !Alloc(n) )
-        {
-            wxFAIL_MSG( _T("out of memory in wxVector::reserve()") );
-        }
+        if ( n <= m_capacity )
+            return;
+
+        // increase the size twice, unless we're already too big or unless
+        // more is requested
+        //
+        // NB: casts to size_type are needed to suppress mingw32 warnings about
+        //     mixing enums and ints in the same expression
+        const size_type increment = m_size > 0
+                                     ? wxMin(m_size, (size_type)ALLOC_MAX_SIZE)
+                                     : (size_type)ALLOC_INITIAL_SIZE;
+        if ( m_capacity + increment > n )
+            n = m_capacity + increment;
+
+        m_values = Ops::Realloc(m_values, n * sizeof(value_type), m_size);
+        m_capacity = n;

     }
 
     size_type size() const
     }
 
     size_type size() const


@@ -76,31 +184,41 @@ public:
 
     wxVector& operator=(const wxVector& vb)
     {
 
     wxVector& operator=(const wxVector& vb)
     {

-        wxCHECK(Copy(vb), *this);
+        Copy(vb);

         return *this;
     }
 
         return *this;
     }
 

-    void push_back(const value_type& o)
+    void push_back(const value_type& v)

     {
     {

-        wxCHECK2(Alloc(size() + 1), return);
-        Append(new value_type(o));
+        reserve(size() + 1);
+
+        // use placement new to initialize new object in preallocated place in
+        // m_values and store 'v' in it:
+        void* const place = m_values + m_size;
+        new(place) value_type(v);
+
+        // only increase m_size if the ctor didn't throw an exception; notice
+        // that if it _did_ throw, everything is OK, because we only increased
+        // vector's capacity so far and possibly written some data to
+        // uninitialized memory at the end of m_values
+        m_size++;

     }
 
     void pop_back()
     {
     }
 
     void pop_back()
     {

-        RemoveAt(size() - 1);
+        erase(end() - 1);

     }
 
     const value_type& at(size_type idx) const
     {
         wxASSERT(idx < m_size);
     }
 
     const value_type& at(size_type idx) const
     {
         wxASSERT(idx < m_size);

-        return *m_objects[idx];
+        return m_values[idx];

     }
 
     value_type& at(size_type idx)
     {
         wxASSERT(idx < m_size);
     }
 
     value_type& at(size_type idx)
     {
         wxASSERT(idx < m_size);

-        return *m_objects[idx];
+        return m_values[idx];

     }
 
     const value_type& operator[](size_type idx) const  { return at(idx); }
     }
 
     const value_type& operator[](size_type idx) const  { return at(idx); }


@@ -110,119 +228,121 @@ public:
     const value_type& back() const { return at(size() - 1); }
     value_type& back() { return at(size() - 1); }
 
     const value_type& back() const { return at(size() - 1); }
     value_type& back() { return at(size() - 1); }
 

-    iterator begin() { return m_objects[0]; }
-    iterator end() { return m_objects[size()]; }
+    const_iterator begin() const { return m_values; }
+    iterator begin() { return m_values; }
+    const_iterator end() const { return m_values + size(); }
+    iterator end() { return m_values + size(); }

 
 

-    iterator erase(iterator first, iterator last)
-    {
-        size_type idx = first - begin();
-        RemoveAt(idx, last - first);
-        return begin() + idx;
-    }
-    iterator erase(iterator it)
-    { 
-        size_type idx = it - begin();
-        RemoveAt(idx);
-        return begin() + idx;
-    }
-    

     iterator insert(iterator it, const value_type& v = value_type())
     {
     iterator insert(iterator it, const value_type& v = value_type())
     {

-        wxCHECK2(Alloc(size() + 1), return 0);
-        size_type idx = it - begin();
-        InsertAt(new value_type(o), idx);
-        return begin() + idx;
-    }
+        // NB: this must be done before reserve(), because reserve()
+        //     invalidates iterators!
+        const size_t idx = it - begin();
+        const size_t after = end() - it;

 
 

-private:
-    bool Alloc(size_type sz)
-    {
-        // work in multiples of m_allocsize;
-        sz = (sz / m_allocsize + 1) * m_allocsize;
-        if (sz <= m_capacity)
-            return true;
+        reserve(size() + 1);

 
 

-        // try to realloc
-        void *mem = realloc(m_objects, sizeof(value_type*) * sz);
-        if (! mem)
-            return false; // failed
-        // success
-        m_objects = (value_type **) mem;
-        m_capacity = sz;
-        return true;
-    }
+        // unless we're inserting at the end, move following elements out of
+        // the way:
+        if ( after > 0 )
+        {
+            Ops::MemmoveForward(m_values + idx + 1, m_values + idx, after);
+        }

 
 

-    void Append(value_type *obj)
-    {
-        wxASSERT(m_size < m_capacity);
-        m_objects[m_size] = obj;
+#if wxUSE_EXCEPTIONS
+        try
+        {
+#endif
+            // use placement new to initialize new object in preallocated place
+            // in m_values and store 'v' in it:
+            void* const place = m_values + idx;
+            new(place) value_type(v);
+#if wxUSE_EXCEPTIONS
+        }
+        catch ( ... )
+        {
+            // if the ctor threw an exception, we need to move all the elements
+            // back to their original positions in m_values
+            if ( after > 0 )
+            {
+                Ops::MemmoveBackward(m_values + idx, m_values + idx + 1, after);
+            }
+
+            throw; // rethrow the exception
+        }
+#endif // wxUSE_EXCEPTIONS
+
+        // increment m_size only if ctor didn't throw -- if it did, we'll be
+        // left with m_values larger than necessary, but number of elements will
+        // be the same

         m_size++;
         m_size++;

+
+        return begin() + idx;

     }
 
     }
 

-    void InsertAt(size_type idx, value_type *obj)
+    iterator erase(iterator it)

     {
     {

-        wxASSERT(idx <= m_size);
-        wxASSERT(m_size < m_capacity);
-        if (idx < m_size)
-            memmove(
-                m_objects + idx + 1,
-                m_objects + idx,
-                ( m_size - idx ) * sizeof(value_type*) );
-        
-        m_size++;
+        return erase(it, it + 1);

     }
 
     }
 

-    void RemoveAt(size_type idx)
+    iterator erase(iterator first, iterator last)

     {
     {

-        wxASSERT(idx < m_size);
-        delete m_objects[idx];
-        if (idx < m_size - 1)
-            memcpy(
-                m_objects + idx,
-                m_objects + idx + 1,
-                ( m_size - idx - 1 ) * sizeof(value_type*) );
-        m_size--;
-    }
-    
-    void RemoveAt(size_type idx, size_type count)
-    {
-        if (count == 0)
-            return;
-        wxASSERT(idx < m_size);
-        size_type i;
-        for (i = 0; i < count; i++)
-            delete m_objects[idx+1];
-        if (idx < m_size - count)
-            memcpy(
-                m_objects + idx,
-                m_objects + idx + count,
-                ( m_size - idx - count ) * sizeof(value_type*) );
+        if ( first == last )
+            return first;
+        wxASSERT( first < end() && last <= end() );
+
+        const size_type idx = first - begin();
+        const size_type count = last - first;
+        const size_type after = end() - last;
+
+        // erase elements by calling their destructors:
+        for ( iterator i = first; i < last; ++i )
+            i->~T();
+
+        // once that's done, move following elements over to the freed space:
+        if ( after > 0 )
+        {
+            Ops::MemmoveBackward(m_values + idx, m_values + idx + count, after);
+        }
+

         m_size -= count;
         m_size -= count;

+
+        return begin() + idx;

     }
     }

-    bool Copy(const wxVector& vb)
+
+#if WXWIN_COMPATIBILITY_2_8
+    wxDEPRECATED( size_type erase(size_type n) );
+#endif // WXWIN_COMPATIBILITY_2_8
+
+private:
+    // VC6 can't compile static const int members
+    enum { ALLOC_INITIAL_SIZE = 16 };
+    enum { ALLOC_MAX_SIZE = 4096 };
+
+    void Copy(const wxVector& vb)

     {
         clear();
     {
         clear();

-        if (! Alloc(vb.size()))
-            return false;
-
-        for (size_type i = 0; i < vb.size(); i++)
-        {
-            value_type *o = new value_type(vb.at(i));
-            if (! o)
-                return false;
-            Append(o);
-        }
+        reserve(vb.size());

 
 

-        return true;
+        for ( const_iterator i = vb.begin(); i != vb.end(); ++i )
+            push_back(*i);

     }
 
 private:
     }
 
 private:

-    size_type m_allocsize;

     size_type m_size,
               m_capacity;
     size_type m_size,
               m_capacity;

-    value_type **m_objects;
+    value_type *m_values;

 };
 
 };
 

+#if WXWIN_COMPATIBILITY_2_8
+template<typename T>
+inline typename wxVector<T>::size_type wxVector<T>::erase(size_type n)
+{
+    erase(begin() + n);
+    return n;
+}
+#endif // WXWIN_COMPATIBILITY_2_8
+

 #endif // wxUSE_STL/!wxUSE_STL
 
 #if WXWIN_COMPATIBILITY_2_8
 #endif // wxUSE_STL/!wxUSE_STL
 
 #if WXWIN_COMPATIBILITY_2_8