Use BufferArea in more places

modules/core/include/opencv2/core/utils/buffer_area.private.hpp

@@ -74,6 +74,25 @@ public:
         allocate_((void**)(&ptr), static_cast<ushort>(sizeof(T)), count, alignment);
     }
 
+    /** @brief Fill one of buffers with zeroes
+
+    @param ptr pointer to memory block previously added using BufferArea::allocate
+
+    BufferArea::commit must be called before using this method
+    */
+    template <typename T>
+    void zeroFill(T*&ptr)
+    {
+        CV_Assert(ptr);
+        zeroFill_((void**)&ptr);
+    }
+
+    /** @brief Fill all buffers with zeroes
+
+    BufferArea::commit must be called before using this method
+    */
+    void zeroFill();
+
     /** @brief Allocate memory and initialize all bound pointers
 
     Each pointer bound to the area with the BufferArea::allocate will be initialized and will be set
@@ -83,10 +102,18 @@ public:
     */
     void commit();
 
+    /** @brief Release all memory and unbind all pointers
+
+    All memory will be freed and all pointers will be reset to NULL and untied from the area allowing
+    to call `allocate` and `commit` again.
+    */
+    void release();
+
 private:
     BufferArea(const BufferArea &); // = delete
     BufferArea &operator=(const BufferArea &); // = delete
     void allocate_(void **ptr, ushort type_size, size_t count, ushort alignment);
+    void zeroFill_(void **ptr);
 
 private:
     class Block;

modules/core/src/buffer_area.cpp

@@ -66,6 +66,16 @@ public:
         *ptr = buf;
         return static_cast<void*>(static_cast<uchar*>(*ptr) + type_size * count);
     }
+    bool operator==(void **other) const
+    {
+        CV_Assert(ptr && other);
+        return *ptr == *other;
+    }
+    void zeroFill() const
+    {
+        CV_Assert(ptr && *ptr);
+        memset(static_cast<uchar*>(*ptr), 0, count * type_size);
+    }
 private:
     void **ptr;
     void * raw_mem;
@@ -85,10 +95,7 @@ BufferArea::BufferArea(bool safe_) :
 
 BufferArea::~BufferArea()
 {
-    for(std::vector<Block>::const_iterator i = blocks.begin(); i != blocks.end(); ++i)
-        i->cleanup();
-    if (oneBuf)
-        fastFree(oneBuf);
+    release();
 }
 
 void BufferArea::allocate_(void **ptr, ushort type_size, size_t count, ushort alignment)
@@ -100,6 +107,26 @@ void BufferArea::allocate_(void **ptr, ushort type_size, size_t count, ushort al
         totalSize += blocks.back().getByteCount();
 }
 
+void BufferArea::zeroFill_(void **ptr)
+{
+    for(std::vector<Block>::const_iterator i = blocks.begin(); i != blocks.end(); ++i)
+    {
+        if (*i == ptr)
+        {
+            i->zeroFill();
+            break;
+        }
+    }
+}
+
+void BufferArea::zeroFill()
+{
+    for(std::vector<Block>::const_iterator i = blocks.begin(); i != blocks.end(); ++i)
+    {
+        i->zeroFill();
+    }
+}
+
 void BufferArea::commit()
 {
     if (!safe)
@@ -116,6 +143,20 @@ void BufferArea::commit()
     }
 }
 
+void BufferArea::release()
+{
+    for(std::vector<Block>::const_iterator i = blocks.begin(); i != blocks.end(); ++i)
+    {
+        i->cleanup();
+    }
+    blocks.clear();
+    if (oneBuf)
+    {
+        fastFree(oneBuf);
+        oneBuf = 0;
+    }
+}
+
 //==================================================================================================
 
 }} // cv::utils::

modules/core/test/test_utils.cpp

@@ -337,6 +337,21 @@ TEST_P(BufferArea, basic)
         ASSERT_TRUE(dbl_ptr != NULL);
         EXPECT_EQ((size_t)0, (size_t)int_ptr % sizeof(int));
         EXPECT_EQ((size_t)0, (size_t)dbl_ptr % sizeof(double));
+        for (size_t i = 0; i < SZ; ++i)
+        {
+            int_ptr[i] = (int)i + 1;
+            uchar_ptr[i] = (uchar)i + 1;
+            dbl_ptr[i] = (double)i + 1;
+        }
+        area.zeroFill(int_ptr);
+        area.zeroFill(uchar_ptr);
+        area.zeroFill(dbl_ptr);
+        for (size_t i = 0; i < SZ; ++i)
+        {
+            EXPECT_EQ((int)0, int_ptr[i]);
+            EXPECT_EQ((uchar)0, uchar_ptr[i]);
+            EXPECT_EQ((double)0, dbl_ptr[i]);
+        }
     }
     EXPECT_TRUE(int_ptr == NULL);
     EXPECT_TRUE(uchar_ptr == NULL);