[UCRT] Import Microsoft.Windows.SDK.CRTSource version 10.0.22621.3

Imported from https://www.nuget.org/packages/Microsoft.Windows.SDK.CRTSource/10.0.22621.3
License: MIT

sdk/lib/ucrt/heap/realloc_base.cpp

@@ -0,0 +1,59 @@
+//
+// realloc_base.cpp
+//
+//      Copyright (c) Microsoft Corporation. All rights reserved.
+//
+// Implementation of _realloc_base().  This is defined in a different source
+// file from the realloc() function to allow realloc() to be replaced by the
+// user.
+//
+#include <corecrt_internal.h>
+#include <malloc.h>
+#include <new.h>
+
+
+
+// This function implements the logic of realloc().  It is called directly by
+// the realloc() and _recalloc() functions in the Release CRT and is called by
+// the debug heap in the Debug CRT.
+//
+// This function must be marked noinline, otherwise realloc and
+// _realloc_base will have identical COMDATs, and the linker will fold
+// them when calling one from the CRT. This is necessary because realloc
+// needs to support users patching in custom implementations.
+extern "C" __declspec(noinline) _CRTRESTRICT void* __cdecl _realloc_base(
+    void*  const block,
+    size_t const size
+    )
+{
+    // If the block is a nullptr, just call malloc:
+    if (block == nullptr)
+        return _malloc_base(size);
+
+    // If the new size is 0, just call free and return nullptr:
+    if (size == 0)
+    {
+        _free_base(block);
+        return nullptr;
+    }
+
+    // Ensure that the requested size is not too large:
+    _VALIDATE_RETURN_NOEXC(_HEAP_MAXREQ >= size, ENOMEM, nullptr);
+
+    for (;;)
+    {
+        void* const new_block = HeapReAlloc(__acrt_heap, 0, block, size);
+        if (new_block)
+            return new_block;
+
+        // Otherwise, see if we need to call the new handler, and if so call it.
+        // If the new handler fails, just return nullptr:
+        if (_query_new_mode() == 0 || !_callnewh(size))
+        {
+            errno = ENOMEM;
+            return nullptr;
+        }
+
+        // The new handler was successful; try to allocate again...
+    }
+}