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-rw-r--r--wcsmbs/wcsstr.c97
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diff --git a/wcsmbs/wcsstr.c b/wcsmbs/wcsstr.c
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+/* Copyright (C) 1995, 1996 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 Library General Public License as
+published by the Free Software Foundation; either version 2 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
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.	 If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+/*
+ * The original strstr() file contains the following comment:
+ *
+ * My personal strstr() implementation that beats most other algorithms.
+ * Until someone tells me otherwise, I assume that this is the
+ * fastest implementation of strstr() in C.
+ * I deliberately chose not to comment it.  You should have at least
+ * as much fun trying to understand it, as I had to write it :-).
+ *
+ * Stephen R. van den Berg, berg@pool.informatik.rwth-aachen.de */
+
+#include <wchar.h>
+
+wchar_t *
+wcsstr (haystack, needle)
+     const wchar_t *haystack;
+     const wchar_t *needle;
+{
+  register wchar_t b, c;
+
+  if ((b = *needle) != L'\0')
+    {
+      haystack--;				/* possible ANSI violation */
+      do
+	if ((c = *++haystack) == L'\0')
+	  goto ret0;
+      while (c != b);
+
+      if (!(c = *++needle))
+	goto foundneedle;
+      ++needle;
+      goto jin;
+
+      for (;;)
+	{
+	  register wchar_t a;
+	  register const wchar_t *rhaystack, *rneedle;
+
+	  do
+	    {
+	      if (!(a = *++haystack))
+		goto ret0;
+	      if (a == b)
+		break;
+	      if ((a = *++haystack) == L'\0')
+		goto ret0;
+shloop:	      ;
+	    }
+	  while (a != b);
+
+jin:	  if (!(a = *++haystack))
+	    goto ret0;
+
+	  if (a != c)
+	    goto shloop;
+
+	  if (*(rhaystack = haystack-- + 1) == (a = *(rneedle = needle)))
+	    do
+	      {
+		if (a == L'\0')
+		  goto foundneedle;
+		if (*++rhaystack != (a = *++needle))
+		  break;
+		if (a == L'\0')
+		  goto foundneedle;
+	      }
+	    while (*++rhaystack == (a = *++needle));
+
+	  needle = rneedle;		  /* took the register-poor approach */
+
+	  if (a == L'\0')
+	    break;
+	}
+    }
+foundneedle:
+  return (wchar_t*) haystack;
+ret0:
+  return NULL;
+}