PDCLIB-2: Pure wide character functions

[pdclib.old] / functions / wchar / wcsncpy.c

diff --git a/functions/wchar/wcsncpy.c b/functions/wchar/wcsncpy.c
new file mode 100644 (file)
index 0000000..6d0e4d2
--- /dev/null
+++ b/functions/wchar/wcsncpy.c
@@ -0,0 +1,43 @@
+/* wchar_t * wcsncpy( wchar_t restrict *, const wchar_t restrict * , size_t );\r
+\r
+   This file is part of the Public Domain C Library (PDCLib).\r
+   Permission is granted to use, modify, and / or redistribute at will.\r
+*/\r
+\r
+#include <wchar.h>\r
+\r
+#ifndef REGTEST\r
+\r
+wchar_t *wcsncpy( wchar_t * _PDCLIB_restrict s1, \r
+                  const wchar_t * _PDCLIB_restrict s2,\r
+                  size_t n )\r
+{\r
+    wchar_t * rc = s1;\r
+    while ( ( n > 0 ) && ( *s1++ = *s2++ ) )\r
+    {\r
+        /* Cannot do "n--" in the conditional as size_t is unsigned and we have\r
+           to check it again for >0 in the next loop below, so we must not risk\r
+           underflow.\r
+        */\r
+        --n;\r
+    }\r
+    /* Checking against 1 as we missed the last --n in the loop above. */\r
+    while ( n-- > 1 )\r
+    {\r
+        *s1++ = '\0';\r
+    }\r
+    return rc;\r
+}\r
+\r
+\r
+#endif\r
+\r
+#ifdef TEST\r
+#include <_PDCLIB_test.h>\r
+\r
+int main( void )\r
+{\r
+    return TEST_RESULTS;\r
+}\r
+\r
+#endif\r