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diff --git a/src/include/taler_amount_lib.h b/src/include/taler_amount_lib.h
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+++ b/src/include/taler_amount_lib.h
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+/*
+  This file is part of TALER
+  (C) 2014, 2015 Christian Grothoff (and other contributing authors)
+
+  TALER is free software; you can redistribute it and/or modify it under the
+  terms of the GNU General Public License as published by the Free Software
+  Foundation; either version 3, or (at your option) any later version.
+
+  TALER 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 General Public License for more details.
+
+  You should have received a copy of the GNU General Public License along with
+  TALER; see the file COPYING.  If not, If not, see <http://www.gnu.org/licenses/>
+*/
+/**
+ * @file include/taler_amount_lib.h
+ * @brief amount-representation utility functions
+ * @author Sree Harsha Totakura <sreeharsha@totakura.in>
+ */
+#ifndef TALER_AMOUNT_LIB_H
+#define TALER_AMOUNT_LIB_H
+
+
+/**
+ * Number of characters (plus 1 for 0-termination) we use to
+ * represent currency names (i.e. EUR, USD, etc.).  We use
+ * 8 for alignment (!).
+ */
+#define TALER_CURRENCY_LEN 8
+
+
+GNUNET_NETWORK_STRUCT_BEGIN
+
+
+/**
+ * Amount, encoded for network transmission.
+ */
+struct TALER_AmountNBO
+{
+  /**
+   * Value in the main currency, in NBO.
+   */
+  uint32_t value;
+
+  /**
+   * Additinal fractional value, in NBO.
+   */
+  uint32_t fraction;
+
+  /**
+   * Type of the currency being represented.
+   */
+  char currency[TALER_CURRENCY_LEN];
+};
+
+GNUNET_NETWORK_STRUCT_END
+
+
+/**
+ * Representation of monetary value in a given currency.
+ */
+struct TALER_Amount
+{
+  /**
+   * Value (numerator of fraction)
+   */
+  uint32_t value;
+
+  /**
+   * Fraction (denominator of fraction)
+   */
+  uint32_t fraction;
+
+  /**
+   * Currency string, left adjusted and padded with zeros.
+   */
+  char currency[TALER_CURRENCY_LEN];
+};
+
+
+/**
+ * Parse denomination description, in the format "T : V : F".
+ *
+ * @param str denomination description
+ * @param denom denomination to write the result to
+ * @return #GNUNET_OK if the string is a valid denomination specification,
+ *         #GNUNET_SYSERR if it is invalid.
+ */
+int
+TALER_string_to_amount (const char *str,
+                        struct TALER_Amount *denom);
+
+
+/**
+ * Convert amount from host to network representation.
+ *
+ * @param d amount in host representation
+ * @return amount in network representation
+ */
+struct TALER_AmountNBO
+TALER_amount_hton (struct TALER_Amount d);
+
+
+/**
+ * Convert amount from network to host representation.
+ *
+ * @param d amount in network representation
+ * @return amount in host representation
+ */
+struct TALER_Amount
+TALER_amount_ntoh (struct TALER_AmountNBO dn);
+
+
+/**
+ * Compare the value/fraction of two amounts.  Does not compare the currency,
+ * i.e. comparing amounts with the same value and fraction but different
+ * currency would return 0.
+ *
+ * @param a1 first amount
+ * @param a2 second amount
+ * @return result of the comparison
+ */
+int
+TALER_amount_cmp (struct TALER_Amount a1,
+                  struct TALER_Amount a2);
+
+
+/**
+ * Perform saturating subtraction of amounts.
+ *
+ * @param a1 amount to subtract from
+ * @param a2 amount to subtract
+ * @return (a1-a2) or 0 if a2>=a1
+ */
+struct TALER_Amount
+TALER_amount_subtract (struct TALER_Amount a1,
+                       struct TALER_Amount a2);
+
+
+/**
+ * Perform saturating addition of amounts
+ *
+ * @param a1 first amount to add
+ * @param a2 second amount to add
+ * @return sum of a1 and a2
+ */
+struct TALER_Amount
+TALER_amount_add (struct TALER_Amount a1,
+                  struct TALER_Amount a2);
+
+
+/**
+ * Normalize the given amount.
+ *
+ * @param amout amount to normalize
+ * @return normalized amount
+ */
+struct TALER_Amount
+TALER_amount_normalize (struct TALER_Amount amount);
+
+
+/**
+ * Convert amount to string.
+ *
+ * @param amount amount to convert to string
+ * @return freshly allocated string representation
+ */
+char *
+TALER_amount_to_string (struct TALER_Amount amount);
+
+
+#endif