[glibc/arm/morello/main] aarch64: morello: string: dummy c strcspn

[Szabolcs Nagy <nsz@sourceware.org>]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=51ba9f28a09a90a7203db2c9e8cca5d56873e655

commit 51ba9f28a09a90a7203db2c9e8cca5d56873e655
Author: Szabolcs Nagy <szabolcs.nagy@arm.com>
Date:   Wed Mar 16 10:59:17 2022 +0000

    aarch64: morello: string: dummy c strcspn
    
    avoids out of bounds access of the generic implementation.

Diff:
---
 sysdeps/aarch64/morello/strcspn.c | 35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/sysdeps/aarch64/morello/strcspn.c b/sysdeps/aarch64/morello/strcspn.c
new file mode 100644
index 0000000000..82c33cdcbf
--- /dev/null
+++ b/sysdeps/aarch64/morello/strcspn.c
@@ -0,0 +1,35 @@
+/* Simple strcspn.
+
+   Copyright (C) 2022 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <string.h>
+
+size_t strcspn (const char *str, const char *reject)
+{
+  if (reject[0] == 0 || reject[1] == 0)
+    return __strchrnul (str, reject[0]) - str;
+
+  unsigned char table[256] = {0};
+  unsigned char *us;
+  for (us = (unsigned char*) reject; *us != 0; table[*us++] = 1);
+  table[*us] = 1;
+
+  for (us = (unsigned char*) str; table[*us] == 0; us++);
+  return us - (unsigned char *) str;
+}
+libc_hidden_builtin_def (strcspn)