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-rw-r--r--REORG.TODO/string/strcspn.c72
1 files changed, 72 insertions, 0 deletions
diff --git a/REORG.TODO/string/strcspn.c b/REORG.TODO/string/strcspn.c
new file mode 100644
index 0000000000..1035552a8e
--- /dev/null
+++ b/REORG.TODO/string/strcspn.c
@@ -0,0 +1,72 @@
+/* Copyright (C) 1991-2017 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 <libc-pointer-arith.h>
+
+#undef strcspn
+
+#ifndef STRCSPN
+# define STRCSPN strcspn
+#endif
+
+/* Return the length of the maximum initial segment of S
+   which contains no characters from REJECT.  */
+size_t
+STRCSPN (const char *str, const char *reject)
+{
+  if (__glibc_unlikely (reject[0] == '\0') ||
+      __glibc_unlikely (reject[1] == '\0'))
+    return __strchrnul (str, reject [0]) - str;
+
+  /* Use multiple small memsets to enable inlining on most targets.  */
+  unsigned char table[256];
+  unsigned char *p = memset (table, 0, 64);
+  memset (p + 64, 0, 64);
+  memset (p + 128, 0, 64);
+  memset (p + 192, 0, 64);
+
+  unsigned char *s = (unsigned char*) reject;
+  unsigned char tmp;
+  do
+    p[tmp = *s++] = 1;
+  while (tmp);
+
+  s = (unsigned char*) str;
+  if (p[s[0]]) return 0;
+  if (p[s[1]]) return 1;
+  if (p[s[2]]) return 2;
+  if (p[s[3]]) return 3;
+
+  s = (unsigned char *) PTR_ALIGN_DOWN (s, 4);
+
+  unsigned int c0, c1, c2, c3;
+  do
+    {
+      s += 4;
+      c0 = p[s[0]];
+      c1 = p[s[1]];
+      c2 = p[s[2]];
+      c3 = p[s[3]];
+    }
+  while ((c0 | c1 | c2 | c3) == 0);
+
+  size_t count = s - (unsigned char *) str;
+  return (c0 | c1) != 0 ? count - c0 + 1 : count - c2 + 3;
+}
+libc_hidden_builtin_def (strcspn)