[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/string/strdup.cpp

@@ -0,0 +1,61 @@
+//
+// strdup.cpp
+//
+//      Copyright (c) Microsoft Corporation.  All rights reserved.
+//
+// Defines _strdup() and _strdup_dbg(), which dynamically allocate a buffer and
+// duplicate a string into it.
+//
+// These functions allocate storage via malloc() or _malloc_dbg().  The caller
+// is responsible for free()ing the returned array.  If the input string is null
+// or if sufficient memory could not be allocated, these functions return null.
+//
+#include <corecrt_internal.h>
+#include <malloc.h>
+#include <string.h>
+
+
+
+#ifdef _DEBUG
+
+extern "C" char* __cdecl _strdup(char const* const string)
+{
+    return _strdup_dbg(string, _NORMAL_BLOCK, nullptr, 0);
+}
+
+extern "C" char* __cdecl _strdup_dbg(
+    char const* const string,
+    int         const block_use,
+    char const* const file_name,
+    int         const line_number
+    )
+
+#else // ^^^ _DEBUG ^^^ // vvv !_DEBUG vvv //
+
+extern "C" char* __cdecl _strdup(
+    char const* string
+    )
+
+#endif // !_DEBUG
+{
+    if (string == nullptr)
+        return nullptr;
+
+    size_t const size = strlen(string) + 1;
+
+#ifdef _DEBUG
+    char* const memory = static_cast<char*>(_malloc_dbg(
+        size,
+        block_use,
+        file_name,
+        line_number));
+#else
+    char* const memory = static_cast<char*>(malloc(size));
+#endif
+    
+    if (memory == nullptr)
+        return nullptr;
+
+    _ERRCHECK(strcpy_s(memory, size, string));
+    return memory;
+}