Move libc replacement files from src/backend/port to src/port.

src/port/strdup.c

@@ -0,0 +1,26 @@
+/*-------------------------------------------------------------------------
+ *
+ * strdup.c
+ *	  copies a null-terminated string.
+ *
+ * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ *	  $Header: /cvsroot/pgsql/src/port/strdup.c,v 1.1 2002/07/18 04:13:59 momjian Exp $
+ *
+ *-------------------------------------------------------------------------
+ */
+#include <string.h>
+#include <stdlib.h>
+#include "strdup.h"
+
+char *
+strdup(char const * string)
+{
+	char	   *nstr;
+
+	nstr = strcpy((char *) malloc(strlen(string) + 1), string);
+	return nstr;
+}