[Boost-commit] svn:boost r72780 - sandbox/SOC/2011/checks/boost/checks

Subject: [Boost-commit] svn:boost r72780 - sandbox/SOC/2011/checks/boost/checks
From: pierre.talbot.6114_at_[hidden]
Date: 2011-06-28 05:00:52

Author: trademark
Date: 2011-06-28 05:00:51 EDT (Tue, 28 Jun 2011)
New Revision: 72780
URL: http://svn.boost.org/trac/boost/changeset/72780

Log:
Modulus file aimed to be the base of numerous other function such as the check digit of VISA, ISBN, EAN, etc...

Currently contains 3 functions related to 3 algorithms (Mod10, mod11, Luhn). 
Added:
   sandbox/SOC/2011/checks/boost/checks/modulus.hpp   (contents, props changed)

Added: sandbox/SOC/2011/checks/boost/checks/modulus.hpp
==============================================================================
--- (empty file)
+++ sandbox/SOC/2011/checks/boost/checks/modulus.hpp	2011-06-28 05:00:51 EDT (Tue, 28 Jun 2011)
@@ -0,0 +1,119 @@
+//  Boost checks/modulus.hpp header file  ------------------------------------//
+//  (C) Copyright Pierre Talbot 2011
+//  Distributed under the Boost Software License, Version 1.0. (See
+//  accompanying file LICENSE_1_0.txt or copy at
+//  http://www.boost.org/LICENSE_1_0.txt
+//  See http://www.boost.org for updates, documentation, and revision history.
+
+#ifndef BOOST_CHECK_MOD_INCLUDED
+#define BOOST_CHECK_MOD_INCLUDED
+
+namespace boost {
+    namespace checks{
+
+/** Validate the check digit of the number provided with the Luhn algorithm.
+ * \tparam Iterator which represents the beginning or the ending of a sequence of character.<br> unsigned int which represents a size.
+ * \param [in] begin Represents the beginning of the sequence to check.
+ * \param [in] end Represents one off the limit of the sequence to check.
+ * \param [unsigned int] nbr_digits Represents the number of digits on which the Luhn algorithm will operate. If the size is < 1, the luhn algorithm will validate the check digit with all the digit encountered.
+ * \pre begin and end are valid initialized iterators. They represent a sequence of character encoded in big-endian mode in a format compatible with the 7 bits ASCII.
+ * \post begin and end are unchanged.
+ * \result end is returned if the number of digits found is less or equals to 1 or not equals to nbr_digits.<br> begin is returned if the check digit of the sequence is not valid.<br> An iterator on the check digit is returned if the sequence is valid.
+ */
+template <class In>
+inline In check_luhn(const In &begin, const In &end, unsigned int nbr_digits)
+{
+  In iter = begin;
+  // If the number of digits isn't given, we compute it.
+  if(!nbr_digits)
+  {
+	while(iter != end)
+	{
+      if(*iter >= '0' && *iter <= '9')
+        ++nbr_digits;
+	  ++iter;
+	}
+	// Return end if the number of digit is equals to 0.
+	if(!nbr_digits)
+	  return end;
+	iter = begin;
+  }
+  int sum = 0,v;
+  while(nbr_digits > 0 && iter != end)
+  {
+    if(*iter >= '0' && *iter <= '9')
+		sum += (v= (*iter & 15) << (--nbr_digits&1)) - 9 * (v>9);
+	++iter;
+  }
+  // Return end if the number of digit isn't equal to the number specified.
+  if(nbr_digits)
+    return end;
+  // Return begin if the sum is invalid
+  // Return iter if the sum is valid
+  return (sum % 10) ? begin : --iter ;
+}
+
+/** Validate the check digit of the number provided with the modulus 11 algorithm.
+ * \tparam Iterator which represents the beginning or the ending of a sequence of character.<br> Int which represents a size.
+ * \param [in] begin Represents the beginning of the sequence to check.
+ * \param [in] end Represents one off the limit of the sequence to check.
+ * \param [int] nbr_digits Represents the number of digits on which the modulus 11 algorithm will operate. If the size is < 1, the modulus 11 algorithm will validate the check digit with all the digit encountered.
+ * \pre begin and end are valid initialized iterators. They represent a sequence of character encoded in big-endian mode in a format compatible with the 7 bits ASCII.
+ * \post begin and end are unchanged.
+ * \result end is returned if the number of digits found is less or equals to 1 or not equals to nbr_digits.<br> begin is returned if the check digit of the sequence is not valid.<br> An iterator on the check digit is returned if the sequence is valid.
+ */
+template <class In>
+inline In check_mod11(In begin, In end, unsigned int nbr_digits)
+{
+  In iter = begin;
+  // If the number of digits isn't given, we compute it.
+  if(nbr_digits == 0)
+  {
+	while(iter != end)
+      if(*iter++ >= '0' && *iter <= '9')
+        ++nbr_digits;
+	iter = begin;
+  }
+  int sum = 0;
+  // Sum the n-1 first digit with a weigth of n
+  while(nbr_digits > 1 && iter != end)
+  {
+    if(*iter >= '0' && *iter <= '9')
+	  sum += *iter & 15 * nbr_digits--;
+	++iter;
+  }
+  // Add the check digit to the sum (add 10 if the check digit equals 'x' or 'X')
+  while(nbr_digits && iter != end)
+  {
+    if(*iter >= '0' && *iter <= '9')
+	{
+	  sum += *iter & 15;
+	  --nbr_digits;
+    }
+	else if(*iter == 'x' || *iter == 'X')
+	{
+	  sum += 10;
+	  --nbr_digits;
+	}
+	else
+	  ++iter;
+  }
+  // Return end if the number of digit isn't equal to the number specified.
+  if(nbr_digits)
+    return end;
+  // Return begin if the sum is invalid
+  // Return iter if the sum is valid
+  return (sum % 11) ? begin : --iter ;
+}
+
+template <class In>
+inline In check_mod10(In begin, In end, unsigned int nbr_digits, unsigned int weight)
+{
+  return begin;
+}
+
+} // namespace checks
+} // namespace boost
+
+#endif // #define BOOST_CHECK_MOD_INCLUDED
+