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Diffstat (limited to 'REORG.TODO/sysdeps/tile/tilegx/strnlen.c')
-rw-r--r--REORG.TODO/sysdeps/tile/tilegx/strnlen.c57
1 files changed, 57 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/tile/tilegx/strnlen.c b/REORG.TODO/sysdeps/tile/tilegx/strnlen.c
new file mode 100644
index 0000000000..5d73a14926
--- /dev/null
+++ b/REORG.TODO/sysdeps/tile/tilegx/strnlen.c
@@ -0,0 +1,57 @@
+/* Copyright (C) 2013-2017 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
+ <http://www.gnu.org/licenses/>. */
+
+#include <string.h>
+#include <stdint.h>
+#include "string-endian.h"
+
+/* Find the length of S, but scan at most MAXLEN characters. If no
+ '\0' terminator is found in that many characters, return MAXLEN. */
+size_t
+__strnlen (const char *s, size_t maxlen)
+{
+ /* When maxlen is 0, can't read any bytes or it might cause a page fault. */
+ if (maxlen == 0)
+ return 0;
+
+ /* Get an aligned pointer. */
+ const uintptr_t s_int = (uintptr_t) s;
+ const uint64_t *p = (const uint64_t *) (s_int & -8);
+ size_t bytes_read = sizeof (*p) - (s_int & (sizeof (*p) - 1));
+
+ /* Read and MASK the first word. */
+ uint64_t v = *p | MASK (s_int);
+
+ uint64_t bits;
+ while ((bits = __insn_v1cmpeqi (v, 0)) == 0)
+ {
+ if (bytes_read >= maxlen)
+ {
+ /* Read maxlen bytes and didn't find the terminator. */
+ return maxlen;
+ }
+ v = *++p;
+ bytes_read += sizeof (v);
+ }
+
+ /* Found '\0', check it is not larger than maxlen */
+ size_t len = ((const char *) p) + (CFZ (bits) >> 3) - s;
+ return (len < maxlen ? len : maxlen);
+}
+libc_hidden_def (__strnlen)
+weak_alias (__strnlen, strnlen)
+libc_hidden_def (strnlen)