1 files changed, 71 insertions, 0 deletions
diff --git a/src/pal/src/safecrt/tcsncpy_s.inl b/src/pal/src/safecrt/tcsncpy_s.inl
new file mode 100644
index 0000000000..54a79a03e7
--- /dev/null
+++ b/src/pal/src/safecrt/tcsncpy_s.inl
@@ -0,0 +1,71 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+/***
+*tcsncpy_s.inl - general implementation of _tcsncpy_s
+*
+
+*
+*Purpose:
+*       This file contains the general algorithm for strncpy_s and its variants.
+*
+****/
+
+_FUNC_PROLOGUE
+errno_t __cdecl _FUNC_NAME(_CHAR *_DEST, size_t _SIZE, const _CHAR *_SRC, size_t _COUNT)
+{
+    _CHAR *p;
+    size_t available;
+
+    if (_COUNT == 0 && _DEST == NULL && _SIZE == 0)
+    {
+        /* this case is allowed; nothing to do */
+        _RETURN_NO_ERROR;
+    }
+
+    /* validation section */
+    _VALIDATE_STRING(_DEST, _SIZE);
+    if (_COUNT == 0)
+    {
+        /* notice that the source string pointer can be NULL in this case */
+        _RESET_STRING(_DEST, _SIZE);
+        _RETURN_NO_ERROR;
+    }
+    _VALIDATE_POINTER_RESET_STRING(_SRC, _DEST, _SIZE);
+
+    p = _DEST;
+    available = _SIZE;
+    if (_COUNT == _TRUNCATE)
+    {
+        while ((*p++ = *_SRC++) != 0 && --available > 0)
+        {
+        }
+    }
+    else
+    {
+        _ASSERT_EXPR((!_CrtGetCheckCount() || _COUNT < _SIZE), "Buffer is too small");
+
+        while ((*p++ = *_SRC++) != 0 && --available > 0 && --_COUNT > 0)
+        {
+        }
+        if (_COUNT == 0)
+        {
+            *p = 0;
+        }
+    }
+
+    if (available == 0)
+    {
+        if (_COUNT == _TRUNCATE)
+        {
+            _DEST[_SIZE - 1] = 0;
+            _RETURN_TRUNCATE;
+        }
+        _RESET_STRING(_DEST, _SIZE);
+        _RETURN_BUFFER_TOO_SMALL(_DEST, _SIZE);
+    }
+    _FILL_STRING(_DEST, _SIZE, _SIZE - available + 1);
+    _RETURN_NO_ERROR;
+}
+