1. fixed wxVector<T> iterators to actually point to what they're supposed to point to instead of crashing on any use

2. don't allocate memory for every element on the heap, store elements directly in the array instead of storing pointers to them

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@48298 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/vector.h

@@ -28,13 +28,14 @@ public:
     typedef size_t size_type;
     typedef T value_type;
     typedef value_type* iterator;
+    typedef const value_type* const_iterator;
     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)
     {
-        wxCHECK2(Copy(c), return);
+        Copy(c);
     }
 
     ~wxVector()
@@ -44,19 +45,35 @@ public:
 
     void clear()
     {
-        for (size_type i = 0; i < size(); i++)
-            delete m_objects[i];
-        free(m_objects);
-        m_objects = 0;
+        delete[] m_values;
+        m_values = NULL;
         m_size = m_capacity = 0;
     }
 
     void reserve(size_type n)
     {
-        if ( !Alloc(n) )
+        if ( n <= m_capacity )
+            return;
+
+        // increase the size twice, unless we're already too big or unless
+        // more is requested
+        const size_type increment = (m_size > 0)
+                                     ? wxMin(m_size, ALLOC_MAX_SIZE)
+                                     : ALLOC_INITIAL_SIZE;
+        if ( m_capacity + increment > n )
+            n = m_capacity + increment;
+
+        value_type *mem = new value_type[n];
+
+        if ( m_values )
         {
-            wxFAIL_MSG( _T("out of memory in wxVector::reserve()") );
+            for ( size_type i = 0; i < m_size; ++i )
+                mem[i] = m_values[i];
+            delete[] m_values;
         }
+
+        m_values = mem;
+        m_capacity = n;
     }
 
     size_type size() const
@@ -76,31 +93,31 @@ public:
 
     wxVector& operator=(const wxVector& vb)
     {
-        wxCHECK(Copy(vb), *this);
+        Copy(vb);
         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);
+        m_values[m_size++] = v;
     }
 
     void pop_back()
     {
-        RemoveAt(size() - 1);
+        erase(end() - 1);
     }
 
     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);
-        return *m_objects[idx];
+        return m_values[idx];
     }
 
     const value_type& operator[](size_type idx) const  { return at(idx); }
@@ -110,128 +127,83 @@ public:
     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 insert(iterator it, const value_type& v = value_type())
+    {
+        size_t idx = it - begin();
+
+        reserve(size() + 1);
+
+        // unless we're inserting at the end, move following values out of
+        // the way:
+        for ( size_t n = m_size; n != idx; --n )
+            m_values[n] = m_values[n-1];
+
+        m_values[idx] = v;
+        m_size++;
+
+        return begin() + idx;
+    }
+
+    iterator erase(iterator it)
+    {
+        return erase(it, it + 1);
+    }
 
     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;
+        if ( first == last )
+            return first;
+        wxASSERT( first < end() && last <= end() );
+
+        size_type index = first - begin();
+        size_type count = last - first;
+
+        // move the remaining values over to the freed space:
+        for ( iterator i = last; i < end(); ++i )
+            *(i - count) = *i;
+
+        // erase items behind the new end of m_values:
+        for ( iterator i = end() - count; i < end(); ++i )
+            *i = value_type();
+
+        m_size -= count;
+
+        return begin() + index;
     }
 
 #if WXWIN_COMPATIBILITY_2_8
     wxDEPRECATED( size_type erase(size_type n) );
 #endif // WXWIN_COMPATIBILITY_2_8
 
-    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(v), idx);
-        return begin() + idx;
-    }
-
 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;
+    static const size_type ALLOC_INITIAL_SIZE = 16;
+    static const size_type ALLOC_MAX_SIZE = 4096;
 
-        // 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;
-    }
-
-    void Append(value_type *obj)
-    {
-        wxASSERT(m_size < m_capacity);
-        m_objects[m_size] = obj;
-        m_size++;
-    }
-
-    void InsertAt(size_type idx, value_type *obj)
-    {
-        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++;
-    }
-
-    void RemoveAt(size_type idx)
-    {
-        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*) );
-        m_size -= count;
-    }
-    bool Copy(const wxVector& vb)
+    void Copy(const wxVector& vb)
     {
         clear();
-        if (! Alloc(vb.size()))
-            return false;
+        reserve(vb.size());
 
-        for (size_type i = 0; i < vb.size(); i++)
-        {
-            value_type *o = new value_type(vb.at(i));
-            if (! o)
-                return false;
-            Append(o);
-        }
-
-        return true;
+        for ( const_iterator i = vb.begin(); i != vb.end(); ++i )
+            push_back(*i);
     }
 
 private:
-    size_type m_allocsize;
     size_type m_size,
               m_capacity;
-    value_type **m_objects;
+    value_type *m_values;
 };
 
 #if WXWIN_COMPATIBILITY_2_8
 template<typename T>
 typename wxVector<T>::size_type wxVector<T>::erase(size_type n)
 {
-    RemoveAt(n);
+    erase(begin() + n);
     return n;
 }
 #endif // WXWIN_COMPATIBILITY_2_8