[libc-commits] [libc] [libc] wcsspn implementation (PR #142034)

[Michael Jones via libc-commits]

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@@ -0,0 +1,34 @@
+//===-- Implementation of wcsspn ------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/wchar/wcsspn.h"
+
+#include "hdr/types/size_t.h"
+#include "hdr/types/wchar_t.h"
+#include "src/__support/common.h"
+#include "src/__support/macros/config.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+LLVM_LIBC_FUNCTION(size_t, wcsspn, (const wchar_t *s1, const wchar_t *s2)) {
+  size_t i = 0;
+  int in_s2 = 0;
+  for (; s1[i]; ++i) {
+    for (int n = 0; s2[n] && in_s2 == 0; ++n) {
+      if (s1[i] == s2[n])
+        in_s2 = 1;
+    }
----------------
michaelrj-google wrote:

if you break the check for if `s1[i]` is in `s2` out into a helper function this will be easier to understand.

https://github.com/llvm/llvm-project/pull/142034