major rename-fest for more constent symbol names

8 files changed, 1320 insertions, 98 deletions

diff --git a/src/include/Makefile.am b/src/include/Makefile.am
index 60f8a3491..4d4c6771e 100644
--- a/src/include/Makefile.am
+++ b/src/include/Makefile.am
@@ -8,4 +8,6 @@ talerinclude_HEADERS = \
   taler_json_lib.h \
   taler_util.h \
   taler_mint_service.h \
+  taler_mintdb_plugin.h \
+  taler_pq_lib.h \
   taler_signatures.h
diff --git a/src/include/taler_crypto_lib.h b/src/include/taler_crypto_lib.h
index 3156e63ed..cfd588a52 100644
--- a/src/include/taler_crypto_lib.h
+++ b/src/include/taler_crypto_lib.h
@@ -32,7 +32,7 @@ GNUNET_NETWORK_STRUCT_BEGIN
 /**
  * Type of public keys for Taler reserves.
  */
-struct TALER_ReservePublicKey
+struct TALER_ReservePublicKeyP
 {
   /**
    * Taler uses EdDSA for reserves.
@@ -44,7 +44,7 @@ struct TALER_ReservePublicKey
 /**
  * Type of private keys for Taler reserves.
  */
-struct TALER_ReservePrivateKey
+struct TALER_ReservePrivateKeyP
 {
   /**
    * Taler uses EdDSA for reserves.
@@ -56,7 +56,7 @@ struct TALER_ReservePrivateKey
 /**
  * Type of signatures used with Taler reserves.
  */
-struct TALER_ReserveSignature
+struct TALER_ReserveSignatureP
 {
   /**
    * Taler uses EdDSA for reserves.
@@ -70,7 +70,7 @@ struct TALER_ReserveSignature
  * Merchants can issue refunds using the corresponding
  * private key.
  */
-struct TALER_MerchantPublicKey
+struct TALER_MerchantPublicKeyP
 {
   /**
    * Taler uses EdDSA for merchants.
@@ -84,7 +84,7 @@ struct TALER_MerchantPublicKey
  * Merchants can issue refunds using the corresponding
  * private key.
  */
-struct TALER_MerchantPrivateKey
+struct TALER_MerchantPrivateKeyP
 {
   /**
    * Taler uses EdDSA for merchants.
@@ -97,7 +97,7 @@ struct TALER_MerchantPrivateKey
  * Type of transfer public keys used during refresh
  * operations.
  */
-struct TALER_TransferPublicKey
+struct TALER_TransferPublicKeyP
 {
   /**
    * Taler uses ECDSA for transfer keys.
@@ -111,7 +111,7 @@ struct TALER_TransferPublicKey
  * Type of transfer public keys used during refresh
  * operations.
  */
-struct TALER_TransferPrivateKey
+struct TALER_TransferPrivateKeyP
 {
   /**
    * Taler uses ECDSA for melting session keys.
@@ -125,7 +125,7 @@ struct TALER_TransferPrivateKey
  * Type of online public keys used by the mint to sign
  * messages.
  */
-struct TALER_MintPublicKey
+struct TALER_MintPublicKeyP
 {
   /**
    * Taler uses EdDSA for online mint message signing.
@@ -138,7 +138,7 @@ struct TALER_MintPublicKey
  * Type of online public keys used by the mint to
  * sign messages.
  */
-struct TALER_MintPrivateKey
+struct TALER_MintPrivateKeyP
 {
   /**
    * Taler uses EdDSA for online signatures sessions.
@@ -150,7 +150,7 @@ struct TALER_MintPrivateKey
 /**
  * Type of signatures used by the mint to sign messages online.
  */
-struct TALER_MintSignature
+struct TALER_MintSignatureP
 {
   /**
    * Taler uses EdDSA for online signatures sessions.
@@ -162,7 +162,7 @@ struct TALER_MintSignature
 /**
  * Type of the offline master public key used by the mint.
  */
-struct TALER_MasterPublicKey
+struct TALER_MasterPublicKeyP
 {
   /**
    * Taler uses EdDSA for the long-term offline master key.
@@ -174,7 +174,7 @@ struct TALER_MasterPublicKey
 /**
  * Type of the offline master public keys used by the mint.
  */
-struct TALER_MasterPrivateKey
+struct TALER_MasterPrivateKeyP
 {
   /**
    * Taler uses EdDSA for the long-term offline master key.
@@ -186,7 +186,7 @@ struct TALER_MasterPrivateKey
 /**
  * Type of signatures by the offline master public key used by the mint.
  */
-struct TALER_MasterSignature
+struct TALER_MasterSignatureP
 {
   /**
    * Taler uses EdDSA for the long-term offline master key.
@@ -199,7 +199,7 @@ struct TALER_MasterSignature
 /**
  * Type of public keys for Taler coins.
  */
-struct TALER_CoinSpendPublicKey
+union TALER_CoinSpendPublicKeyP
 {
   /**
    * Taler uses ECDSA for coins.
@@ -211,7 +211,7 @@ struct TALER_CoinSpendPublicKey
 /**
  * Type of private keys for Taler coins.
  */
-struct TALER_CoinSpendPrivateKey
+union TALER_CoinSpendPrivateKeyP
 {
   /**
    * Taler uses ECDSA for coins.
@@ -223,7 +223,7 @@ struct TALER_CoinSpendPrivateKey
 /**
  * Type of signatures made with Taler coins.
  */
-struct TALER_CoinSpendSignature
+union TALER_CoinSpendSignatureP
 {
   /**
    * Taler uses ECDSA for coins.
@@ -294,7 +294,7 @@ struct TALER_CoinPublicInfo
   /**
    * The coin's public key.
    */
-  struct TALER_CoinSpendPublicKey coin_pub;
+  union TALER_CoinSpendPublicKeyP coin_pub;
 
   /**
    * Public key representing the denomination of the coin
@@ -331,10 +331,10 @@ GNUNET_NETWORK_STRUCT_BEGIN
 /**
  * Secret used to decrypt the key to decrypt link secrets.
  */
-struct TALER_TransferSecret
+struct TALER_TransferSecretP
 {
   /**
-   * Secret used to encrypt/decrypt the `struct TALER_LinkSecret`.
+   * Secret used to encrypt/decrypt the `struct TALER_LinkSecretP`.
    * Must be (currently) a hash as this is what
    * #GNUNET_CRYPTO_ecc_ecdh() returns to us.
    */
@@ -345,7 +345,7 @@ struct TALER_TransferSecret
 /**
  * Secret used to decrypt refresh links.
  */
-struct TALER_LinkSecret
+struct TALER_LinkSecretP
 {
   /**
    * Secret used to decrypt the refresh link data.
@@ -357,25 +357,25 @@ struct TALER_LinkSecret
 /**
  * Encrypted secret used to decrypt refresh links.
  */
-struct TALER_EncryptedLinkSecret
+struct TALER_EncryptedLinkSecretP
 {
   /**
    * Encrypted secret, must be the given size!
    */
-  char enc[sizeof (struct TALER_LinkSecret)];
+  char enc[sizeof (struct TALER_LinkSecretP)];
 };
 
 
 /**
  * Representation of an refresh link in cleartext.
  */
-struct TALER_RefreshLinkDecrypted
+struct TALER_RefreshLinkDecryptedP
 {
 
   /**
    * Private key of the coin.
    */
-  struct TALER_CoinSpendPrivateKey coin_priv;
+  union TALER_CoinSpendPrivateKeyP coin_priv;
 
   /**
    * Blinding key.
@@ -408,7 +408,7 @@ struct TALER_RefreshLinkEncrypted
   /**
    * Encrypted private key of the coin.
    */
-  char coin_priv_enc[sizeof (struct TALER_CoinSpendPrivateKey)];
+  char coin_priv_enc[sizeof (union TALER_CoinSpendPrivateKeyP)];
 
 };
 
@@ -423,9 +423,9 @@ struct TALER_RefreshLinkEncrypted
  * @return #GNUNET_OK on success
  */
 int
-TALER_transfer_decrypt (const struct TALER_EncryptedLinkSecret *secret_enc,
-                        const struct TALER_TransferSecret *trans_sec,
-                        struct TALER_LinkSecret *secret);
+TALER_transfer_decrypt (const struct TALER_EncryptedLinkSecretP *secret_enc,
+                        const struct TALER_TransferSecretP *trans_sec,
+                        struct TALER_LinkSecretP *secret);
 
 
 /**
@@ -438,9 +438,9 @@ TALER_transfer_decrypt (const struct TALER_EncryptedLinkSecret *secret_enc,
  * @return #GNUNET_OK on success
  */
 int
-TALER_transfer_encrypt (const struct TALER_LinkSecret *secret,
-                        const struct TALER_TransferSecret *trans_sec,
-                        struct TALER_EncryptedLinkSecret *secret_enc);
+TALER_transfer_encrypt (const struct TALER_LinkSecretP *secret,
+                        const struct TALER_TransferSecretP *trans_sec,
+                        struct TALER_EncryptedLinkSecretP *secret_enc);
 
 
 /**
@@ -450,9 +450,9 @@ TALER_transfer_encrypt (const struct TALER_LinkSecret *secret,
  * @param secret shared secret to use for decryption
  * @return NULL on error
  */
-struct TALER_RefreshLinkDecrypted *
+struct TALER_RefreshLinkDecryptedP *
 TALER_refresh_decrypt (const struct TALER_RefreshLinkEncrypted *input,
-                       const struct TALER_LinkSecret *secret);
+                       const struct TALER_LinkSecretP *secret);
 
 
 /**
@@ -463,8 +463,8 @@ TALER_refresh_decrypt (const struct TALER_RefreshLinkEncrypted *input,
  * @return NULL on error (should never happen)
  */
 struct TALER_RefreshLinkEncrypted *
-TALER_refresh_encrypt (const struct TALER_RefreshLinkDecrypted *input,
-                       const struct TALER_LinkSecret *secret);
+TALER_refresh_encrypt (const struct TALER_RefreshLinkDecryptedP *input,
+                       const struct TALER_LinkSecretP *secret);
 
 
 /**
diff --git a/src/include/taler_json_lib.h b/src/include/taler_json_lib.h
index c5515966f..dbf2293d0 100644
--- a/src/include/taler_json_lib.h
+++ b/src/include/taler_json_lib.h
@@ -18,15 +18,15 @@
  * @brief helper functions for JSON processing using libjansson
  * @author Sree Harsha Totakura <sreeharsha@totakura.in>
  */
-#ifndef TALER_JSON_LIB_H_
-#define TALER_JSON_LIB_H_
+#ifndef TALER_json_LIB_H_
+#define TALER_json_LIB_H_
 
 #include <jansson.h>
 
 /**
  * Print JSON parsing related error information
  */
-#define TALER_JSON_warn(error)                                         \
+#define TALER_json_warn(error)                                         \
   GNUNET_log (GNUNET_ERROR_TYPE_WARNING,                                \
               "JSON parsing failed at %s:%u: %s (%s)\n",                  \
               __FILE__, __LINE__, error.text, error.source)
@@ -39,7 +39,7 @@
  * @return a json object describing the amount
  */
 json_t *
-TALER_JSON_from_amount (const struct TALER_Amount *amount);
+TALER_json_from_amount (const struct TALER_Amount *amount);
 
 
 /**
@@ -49,7 +49,7 @@ TALER_JSON_from_amount (const struct TALER_Amount *amount);
  * @return a json string with the timestamp in @a stamp
  */
 json_t *
-TALER_JSON_from_abs (struct GNUNET_TIME_Absolute stamp);
+TALER_json_from_abs (struct GNUNET_TIME_Absolute stamp);
 
 
 /**
@@ -60,7 +60,7 @@ TALER_JSON_from_abs (struct GNUNET_TIME_Absolute stamp);
  * @return the JSON reporesentation of the signature with purpose
  */
 json_t *
-TALER_JSON_from_eddsa_sig (const struct GNUNET_CRYPTO_EccSignaturePurpose *purpose,
+TALER_json_from_eddsa_sig (const struct GNUNET_CRYPTO_EccSignaturePurpose *purpose,
                            const struct GNUNET_CRYPTO_EddsaSignature *signature);
 
 
@@ -72,7 +72,7 @@ TALER_JSON_from_eddsa_sig (const struct GNUNET_CRYPTO_EccSignaturePurpose *purpo
  * @return the JSON reporesentation of the signature with purpose
  */
 json_t *
-TALER_JSON_from_ecdsa_sig (const struct GNUNET_CRYPTO_EccSignaturePurpose *purpose,
+TALER_json_from_ecdsa_sig (const struct GNUNET_CRYPTO_EccSignaturePurpose *purpose,
                            const struct GNUNET_CRYPTO_EcdsaSignature *signature);
 
 
@@ -83,7 +83,7 @@ TALER_JSON_from_ecdsa_sig (const struct GNUNET_CRYPTO_EccSignaturePurpose *purpo
  * @return corresponding JSON encoding
  */
 json_t *
-TALER_JSON_from_rsa_public_key (struct GNUNET_CRYPTO_rsa_PublicKey *pk);
+TALER_json_from_rsa_public_key (struct GNUNET_CRYPTO_rsa_PublicKey *pk);
 
 
 /**
@@ -93,7 +93,7 @@ TALER_JSON_from_rsa_public_key (struct GNUNET_CRYPTO_rsa_PublicKey *pk);
  * @return corresponding JSON encoding
  */
 json_t *
-TALER_JSON_from_rsa_signature (struct GNUNET_CRYPTO_rsa_Signature *sig);
+TALER_json_from_rsa_signature (struct GNUNET_CRYPTO_rsa_Signature *sig);
 
 
 /**
@@ -105,7 +105,7 @@ TALER_JSON_from_rsa_signature (struct GNUNET_CRYPTO_rsa_Signature *sig);
  * @return json string that encodes @a data
  */
 json_t *
-TALER_JSON_from_data (const void *data, size_t size);
+TALER_json_from_data (const void *data, size_t size);
 
 
 /**
@@ -116,7 +116,7 @@ TALER_JSON_from_data (const void *data, size_t size);
  * @return json string that encodes @a hc
  */
 json_t *
-TALER_JSON_from_hash (const struct GNUNET_HashCode *hc);
+TALER_json_from_hash (const struct GNUNET_HashCode *hc);
 
 
 /**
@@ -127,7 +127,7 @@ TALER_JSON_from_hash (const struct GNUNET_HashCode *hc);
  * @return #GNUNET_OK upon successful parsing; #GNUNET_SYSERR upon error
  */
 int
-TALER_JSON_to_amount (json_t *json,
+TALER_json_to_amount (json_t *json,
                       struct TALER_Amount *r_amount);
 
 /**
@@ -138,7 +138,7 @@ TALER_JSON_to_amount (json_t *json,
  * @return #GNUNET_OK upon successful parsing; #GNUNET_SYSERR upon error
  */
 int
-TALER_JSON_to_abs (json_t *json,
+TALER_json_to_abs (json_t *json,
                    struct GNUNET_TIME_Absolute *r_abs);
 
 /**
@@ -150,7 +150,7 @@ TALER_JSON_to_abs (json_t *json,
  * @return #GNUNET_OK upon successful parsing; #GNUNET_SYSERR upon error
  */
 int
-TALER_JSON_to_data (json_t *json,
+TALER_json_to_data (json_t *json,
                     void *out,
                     size_t out_size);
 
@@ -162,10 +162,10 @@ TALER_JSON_to_data (json_t *json,
  * @return #GNUNET_YES if correctly formatted; #GNUNET_NO if not
  */
 int
-TALER_JSON_validate_wireformat (const char *type,
+TALER_json_validate_wireformat (const char *type,
                                 const json_t *wire);
 
 
-#endif /* TALER_JSON_LIB_H_ */
+#endif /* TALER_json_LIB_H_ */
 
 /* End of taler_json_lib.h */
diff --git a/src/include/taler_mint_service.h b/src/include/taler_mint_service.h
index 30aaad38e..774f40f54 100644
--- a/src/include/taler_mint_service.h
+++ b/src/include/taler_mint_service.h
@@ -42,7 +42,7 @@ struct TALER_MINT_SigningPublicKey
   /**
    * The signing public key
    */
-  struct TALER_MintPublicKey key;
+  struct TALER_MintPublicKeyP key;
 
   /**
    * Validity start time
@@ -140,7 +140,7 @@ struct TALER_MINT_Handle *
 TALER_MINT_connect (struct TALER_MINT_Context *ctx,
                     const char *hostname,
                     uint16_t port,
-                    const struct TALER_MasterPublicKey *master_key);
+                    const struct TALER_MasterPublicKeyP *master_key);
 
 /**
  * Disconnect from the mint
@@ -287,7 +287,7 @@ TALER_MINT_deposit_submit_json_ (struct TALER_MINT_Handle *mint,
                                  struct TALER_BLIND_Signature *ubsig,
                                  uint64_t transaction_id,
                                  struct TALER_Amount *amount,
-                                 const struct TALER_MerchantPublicKey *merchant_pub,
+                                 const struct TALER_MerchantPublicKeyP *merchant_pub,
                                  const struct GNUNET_HashCode *h_contract,
                                  const struct GNUNET_HashCode *h_wire,
                                  const struct TALER_CoinSignature *csig,
diff --git a/src/include/taler_mintdb_plugin.h b/src/include/taler_mintdb_plugin.h
new file mode 100644
index 000000000..8c9f4af23
--- /dev/null
+++ b/src/include/taler_mintdb_plugin.h
@@ -0,0 +1,1029 @@
+/*
+  This file is part of TALER
+  Copyright (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 mint/taler_mintdb_plugin.h
+ * @brief Low-level (statement-level) database access for the mint
+ * @author Florian Dold
+ * @author Christian Grothoff
+ */
+#ifndef TALER_MINTDB_PLUGIN_H
+#define TALER_MINTDB_PLUGIN_H
+
+#include <gnunet/gnunet_util_lib.h>
+#include "taler_util.h"
+
+
+/**
+ * Information we keep on bank transfer(s) that established a reserve.
+ */
+struct BankTransfer
+{
+
+  /**
+   * Public key of the reserve that was filled.
+   */
+  struct TALER_ReservePublicKeyP reserve_pub;
+
+  /**
+   * Amount that was transferred to the mint.
+   */
+  struct TALER_Amount amount;
+
+  /**
+   * Detailed wire information about the transaction.
+   */
+  json_t *wire;
+
+};
+
+
+/**
+ * A summary of a Reserve
+ */
+struct Reserve
+{
+  /**
+   * The reserve's public key.  This uniquely identifies the reserve
+   */
+  struct TALER_ReservePublicKeyP pub;
+
+  /**
+   * The balance amount existing in the reserve
+   */
+  struct TALER_Amount balance;
+
+  /**
+   * The expiration date of this reserve
+   */
+  struct GNUNET_TIME_Absolute expiry;
+};
+
+
+/**
+ * Information we keep for a withdrawn coin to reproduce
+ * the /withdraw operation if needed, and to have proof
+ * that a reserve was drained by this amount.
+ */
+struct CollectableBlindcoin
+{
+
+  /**
+   * Our signature over the (blinded) coin.
+   */
+  struct TALER_DenominationSignature sig;
+
+  /**
+   * Denomination key (which coin was generated).
+   * FIXME: we should probably instead have the
+   * AMOUNT *including* fee in what is being signed
+   * as well!
+   */
+  struct TALER_DenominationPublicKey denom_pub;
+
+  /**
+   * Public key of the reserve that was drained.
+   */
+  struct TALER_ReservePublicKeyP reserve_pub;
+
+  /**
+   * Hash over the blinded message, needed to verify
+   * the @e reserve_sig.
+   */
+  struct GNUNET_HashCode h_coin_envelope;
+
+  /**
+   * Signature confirming the withdrawl, matching @e reserve_pub,
+   * @e denom_pub and @e h_coin_envelope.
+   */
+  struct TALER_ReserveSignatureP reserve_sig;
+};
+
+
+
+/**
+ * Types of operations on a reserved.
+ */
+enum TALER_MINT_DB_ReserveOperation
+{
+  /**
+   * Money was deposited into the reserve via a bank transfer.
+   */
+  TALER_MINT_DB_RO_BANK_TO_MINT = 0,
+
+  /**
+   * A Coin was withdrawn from the reserve using /withdraw.
+   */
+  TALER_MINT_DB_RO_WITHDRAW_COIN = 1
+};
+
+
+/**
+ * Reserve history as a linked list.  Lists all of the transactions
+ * associated with this reserve (such as the bank transfers that
+ * established the reserve and all /withdraw operations we have done
+ * since).
+ */
+struct ReserveHistory
+{
+
+  /**
+   * Next entry in the reserve history.
+   */
+  struct ReserveHistory *next;
+
+  /**
+   * Type of the event, determins @e details.
+   */
+  enum TALER_MINT_DB_ReserveOperation type;
+
+  /**
+   * Details of the operation, depending on @e type.
+   */
+  union
+  {
+
+    /**
+     * Details about a bank transfer to the mint.
+     */
+    struct BankTransfer *bank;
+
+    /**
+     * Details about a /withdraw operation.
+     */
+    struct CollectableBlindcoin *withdraw;
+
+  } details;
+
+};
+
+
+/**
+ * Specification for a /deposit operation.
+ */
+struct Deposit
+{
+  /**
+   * Information about the coin that is being deposited.
+   */
+  struct TALER_CoinPublicInfo coin;
+
+  /**
+   * ECDSA signature affirming that the customer intends
+   * this coin to be deposited at the merchant identified
+   * by @e h_wire in relation to the contract identified
+   * by @e h_contract.
+   */
+  union TALER_CoinSpendSignatureP csig;
+
+  /**
+   * Public key of the merchant.  Enables later identification
+   * of the merchant in case of a need to rollback transactions.
+   */
+  struct TALER_MerchantPublicKeyP merchant_pub;
+
+  /**
+   * Hash over the contract between merchant and customer
+   * (remains unknown to the Mint).
+   */
+  struct GNUNET_HashCode h_contract;
+
+  /**
+   * Hash of the (canonical) representation of @e wire, used
+   * to check the signature on the request.  Generated by
+   * the mint from the detailed wire data provided by the
+   * merchant.
+   */
+  struct GNUNET_HashCode h_wire;
+
+  /**
+   * Detailed wire information for executing the transaction.
+   */
+  json_t *wire;
+
+  /**
+   * Merchant-generated transaction ID to detect duplicate
+   * transactions.
+   */
+  uint64_t transaction_id;
+
+  /**
+   * Fraction of the coin's remaining value to be deposited, including
+   * depositing fee (if any).  The coin is identified by @e coin_pub.
+   */
+  struct TALER_Amount amount_with_fee;
+
+};
+
+
+/**
+ * Global information for a refreshing session.  Includes
+ * dimensions of the operation, security parameters and
+ * client signatures from "/refresh/melt" and "/refresh/commit".
+ */
+struct RefreshSession
+{
+
+  /**
+   * Number of coins we are melting.
+   */
+  uint16_t num_oldcoins;
+
+  /**
+   * Number of new coins we are creating.
+   */
+  uint16_t num_newcoins;
+
+  /**
+   * Index (smaller #TALER_CNC_KAPPA) which the mint has chosen to not
+   * have revealed during cut and choose.
+   */
+  uint16_t noreveal_index;
+
+};
+
+
+/**
+ * Specification for coin in a /refresh/melt operation.
+ */
+struct RefreshMelt
+{
+  /**
+   * Information about the coin that is being melted.
+   */
+  struct TALER_CoinPublicInfo coin;
+
+  /**
+   * Signature over the melting operation.
+   */
+  union TALER_CoinSpendSignatureP coin_sig;
+
+  /**
+   * Hash of the refresh session this coin is melted into.
+   */
+  struct GNUNET_HashCode session_hash;
+
+  /**
+   * How much value is being melted?  This amount includes the fees,
+   * so the final amount contributed to the melt is this value minus
+   * the fee for melting the coin.  We include the fee in what is
+   * being signed so that we can verify a reserve's remaining total
+   * balance without needing to access the respective denomination key
+   * information each time.
+   */
+  struct TALER_Amount amount_with_fee;
+
+};
+
+
+/**
+ * We have as many `struct RefreshCommitCoin` as there are new
+ * coins being created by the refresh (for each of the #TALER_CNC_KAPPA
+ * sets).  These are the coins we ask the mint to sign if the
+ * respective set is selected.
+ */
+struct RefreshCommitCoin
+{
+
+  /**
+   * Encrypted data allowing those able to decrypt it to derive
+   * the private keys of the new coins created by the refresh.
+   */
+  struct TALER_RefreshLinkEncrypted *refresh_link;
+
+  /**
+   * Blinded message to be signed (in envelope), with @e coin_env_size bytes.
+   */
+  char *coin_ev;
+
+  /**
+   * Number of bytes in @e coin_ev.
+   */
+  size_t coin_ev_size;
+
+};
+
+
+GNUNET_NETWORK_STRUCT_BEGIN
+
+/**
+ * For each (old) coin being melted, we have a `struct
+ * RefreshCommitLink` that allows the user to find the shared secret
+ * to decrypt the respective refresh links for the new coins in the
+ * `struct RefreshCommitCoin`.
+ */
+struct RefreshCommitLink
+{
+  /**
+   * Transfer public key, used to decrypt the @e shared_secret_enc
+   * in combintation with the corresponding private key of the
+   * coin.
+   */
+  struct TALER_TransferPublicKeyP transfer_pub;
+
+  /**
+   * Encrypted shared secret to decrypt the link.
+   */
+  struct TALER_EncryptedLinkSecretP shared_secret_enc;
+};
+
+GNUNET_NETWORK_STRUCT_END
+
+
+
+/**
+ * Linked list of refresh information linked to a coin.
+ */
+struct LinkDataList
+{
+  /**
+   * Information is stored in a NULL-terminated linked list.
+   */
+  struct LinkDataList *next;
+
+  /**
+   * Link data, used to recover the private key of the coin
+   * by the owner of the old coin.
+   */
+  struct TALER_RefreshLinkEncrypted *link_data_enc;
+
+  /**
+   * Denomination public key, determines the value of the coin.
+   */
+  struct TALER_DenominationPublicKey denom_pub;
+
+  /**
+   * Signature over the blinded envelope.
+   */
+  struct TALER_DenominationSignature ev_sig;
+};
+
+
+/**
+ * Specification for a /lock operation.
+ */
+struct Lock
+{
+  /**
+   * Information about the coin that is being locked.
+   */
+  struct TALER_CoinPublicInfo coin;
+
+  /**
+   * Signature over the locking operation.
+   */
+  union TALER_CoinSpendSignatureP coin_sig;
+
+  /**
+   * How much value is being locked?
+   */
+  struct TALER_Amount amount;
+
+  // FIXME: more needed...
+};
+
+
+/**
+ * Enumeration to classify the different types of transactions
+ * that can be done with a coin.
+ */
+enum TALER_MINT_DB_TransactionType
+{
+  /**
+   * /deposit operation.
+   */
+  TALER_MINT_DB_TT_DEPOSIT = 0,
+
+  /**
+   * /refresh/melt operation.
+   */
+  TALER_MINT_DB_TT_REFRESH_MELT = 1,
+
+  /**
+   * /lock operation.
+   */
+  TALER_MINT_DB_TT_LOCK = 2
+};
+
+
+/**
+ * List of transactions we performed for a particular coin.
+ */
+struct TALER_MINT_DB_TransactionList
+{
+
+  /**
+   * Next pointer in the NULL-terminated linked list.
+   */
+  struct TALER_MINT_DB_TransactionList *next;
+
+  /**
+   * Type of the transaction, determines what is stored in @e details.
+   */
+  enum TALER_MINT_DB_TransactionType type;
+
+  /**
+   * Details about the transaction, depending on @e type.
+   */
+  union
+  {
+
+    /**
+     * Details if transaction was a /deposit operation.
+     */
+    struct Deposit *deposit;
+
+    /**
+     * Details if transaction was a /refresh/melt operation.
+     */
+    struct RefreshMelt *melt;
+
+    /**
+     * Details if transaction was a /lock operation.
+     */
+    struct Lock *lock;
+
+  } details;
+
+};
+
+
+/**
+ * Handle for a database session (per-thread, for transactions).
+ */
+struct TALER_MINTDB_Session;
+
+
+/**
+ * The plugin API, returned from the plugin's "init" function.
+ * The argument given to "init" is simply a configuration handle.
+ */
+struct TALER_MINTDB_Plugin
+{
+
+  /**
+   * Closure for all callbacks.
+   */
+  void *cls;
+
+  /**
+   * Name of the library which generated this plugin
+   */
+  const char *library_name;
+
+  /**
+   * Get the thread-local database-handle.
+   * Connect to the db if the connection does not exist yet.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param temporary #GNUNET_YES to use a temporary schema; #GNUNET_NO to use the
+   *        database default one
+   * @param the database connection, or NULL on error
+   */
+  struct TALER_MINTDB_Session *
+  (*get_session) (void *cls,
+                  int temporary);
+
+
+  /**
+   * Drop the temporary taler schema.  This is only useful for testcases.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @return #GNUNET_OK upon success; #GNUNET_SYSERR upon failure
+   */
+  int
+  (*drop_temporary) (void *cls,
+                     struct TALER_MINTDB_Session *db);
+
+
+  /**
+   * Create the necessary tables if they are not present
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param temporary should we use a temporary schema
+   * @return #GNUNET_OK upon success; #GNUNET_SYSERR upon failure
+   */
+  int
+  (*create_tables) (void *cls,
+                    int temporary);
+
+
+  /**
+   * Start a transaction.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param sesssion connection to use
+   * @return #GNUNET_OK on success
+   */
+  int
+  (*start) (void *cls,
+            struct TALER_MINTDB_Session *sesssion);
+
+
+  /**
+   * Commit a transaction.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param sesssion connection to use
+   * @return #GNUNET_OK on success
+   */
+  int
+  (*commit) (void *cls,
+             struct TALER_MINTDB_Session *sesssion);
+
+
+  /**
+   * Abort/rollback a transaction.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param sesssion connection to use
+   */
+  void
+  (*rollback) (void *cls,
+               struct TALER_MINTDB_Session *sesssion);
+
+
+  /**
+   * Get the summary of a reserve.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param db the database connection handle
+   * @param reserve the reserve data.  The public key of the reserve should be set
+   *          in this structure; it is used to query the database.  The balance
+   *          and expiration are then filled accordingly.
+   * @return #GNUNET_OK upon success; #GNUNET_SYSERR upon failure
+   */
+  int
+  (*reserve_get) (void *cls,
+                  struct TALER_MINTDB_Session *db,
+                  struct Reserve *reserve);
+
+  /* FIXME: add functions to add bank transfers to our DB
+     (and to test if we already did add one) (#3633/#3717) */
+
+
+  /**
+   * Insert a incoming transaction into reserves.  New reserves are also created
+   * through this function.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param db the database connection handle
+   * @param reserve the reserve structure.  The public key of the reserve should
+   *          be set here.  Upon successful execution of this function, the
+   *          balance and expiration of the reserve will be updated.
+   * @param balance the amount that has to be added to the reserve
+   * @param expiry the new expiration time for the reserve
+   * @return #GNUNET_OK upon success; #GNUNET_SYSERR upon failures
+   */
+  int
+  (*reserves_in_insert) (void *cls,
+                         struct TALER_MINTDB_Session *db,
+                         struct Reserve *reserve,
+                         const struct TALER_Amount *balance,
+                         const struct GNUNET_TIME_Absolute expiry);
+
+
+  /**
+   * Locate the response for a /withdraw request under the
+   * key of the hash of the blinded message.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param sesssion database connection to use
+   * @param h_blind hash of the blinded message
+   * @param collectable corresponding collectable coin (blind signature)
+   *                    if a coin is found
+   * @return #GNUNET_SYSERR on internal error
+   *         #GNUNET_NO if the collectable was not found
+   *         #GNUNET_YES on success
+   */
+  int
+  (*get_collectable_blindcoin) (void *cls,
+                                struct TALER_MINTDB_Session *sesssion,
+                                const struct GNUNET_HashCode *h_blind,
+                                struct CollectableBlindcoin *collectable);
+
+
+  /**
+   * Store collectable bit coin under the corresponding
+   * hash of the blinded message.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param sesssion database connection to use
+   * @param h_blind hash of the blinded message
+   * @param withdraw amount by which the reserve will be withdrawn with this
+   *          transaction
+   * @param collectable corresponding collectable coin (blind signature)
+   *                    if a coin is found
+   * @return #GNUNET_SYSERR on internal error
+   *         #GNUNET_NO if the collectable was not found
+   *         #GNUNET_YES on success
+   */
+  int
+  (*insert_collectable_blindcoin) (void *cls,
+                                   struct TALER_MINTDB_Session *sesssion,
+                                   const struct GNUNET_HashCode *h_blind,
+                                   struct TALER_Amount withdraw,
+                                   const struct CollectableBlindcoin *collectable);
+
+
+  /**
+   * Get all of the transaction history associated with the specified
+   * reserve.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param sesssion connection to use
+   * @param reserve_pub public key of the reserve
+   * @return known transaction history (NULL if reserve is unknown)
+   */
+  struct ReserveHistory *
+  (*get_reserve_history) (void *cls,
+                          struct TALER_MINTDB_Session *sesssion,
+                          const struct TALER_ReservePublicKeyP *reserve_pub);
+
+
+  /**
+   * Free memory associated with the given reserve history.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param rh history to free.
+   */
+  void
+  (*free_reserve_history) (void *cls,
+                           struct ReserveHistory *rh);
+
+
+  /**
+   * Check if we have the specified deposit already in the database.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param sesssion database connection
+   * @param deposit deposit to search for
+   * @return #GNUNET_YES if we know this operation,
+   *         #GNUNET_NO if this deposit is unknown to us,
+   *         #GNUNET_SYSERR on internal error
+   */
+  int
+  (*have_deposit) (void *cls,
+                   struct TALER_MINTDB_Session *sesssion,
+                   const struct Deposit *deposit);
+
+
+  /**
+   * Insert information about deposited coin into the
+   * database.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param sesssion connection to the database
+   * @param deposit deposit information to store
+   * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
+   */
+  int
+  (*insert_deposit) (void *cls,
+                     struct TALER_MINTDB_Session *sesssion,
+                     const struct Deposit *deposit);
+
+
+  /**
+   * Lookup refresh session data under the given @a session_hash.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param sesssion database handle to use
+   * @param session_hash hash over the melt to use for the lookup
+   * @param refresh_session[OUT] where to store the result
+   * @return #GNUNET_YES on success,
+   *         #GNUNET_NO if not found,
+   *         #GNUNET_SYSERR on DB failure
+   */
+  int
+  (*get_refresh_session) (void *cls,
+                          struct TALER_MINTDB_Session *sesssion,
+                          const struct GNUNET_HashCode *session_hash,
+                          struct RefreshSession *refresh_session);
+
+
+  /**
+   * Store new refresh session data under the given @a session_hash.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param sesssion database handle to use
+   * @param session_hash hash over the melt to use to locate the session
+   * @param refresh_session session data to store
+   * @return #GNUNET_YES on success,
+   *         #GNUNET_SYSERR on DB failure
+   */
+  int
+  (*create_refresh_session) (void *cls,
+                             struct TALER_MINTDB_Session *sesssion,
+                             const struct GNUNET_HashCode *session_hash,
+                             const struct RefreshSession *refresh_session);
+
+
+  /**
+   * Store the given /refresh/melt request in the database.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param sesssion database connection
+   * @param oldcoin_index index of the coin to store
+   * @param melt coin melt operation details to store; includes
+   *             the session hash of the melt
+   * @return #GNUNET_OK on success
+   *         #GNUNET_SYSERR on internal error
+   */
+  int
+  (*insert_refresh_melt) (void *cls,
+                          struct TALER_MINTDB_Session *sesssion,
+                          uint16_t oldcoin_index,
+                          const struct RefreshMelt *melt);
+
+
+  /**
+   * Get information about melted coin details from the database.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param sesssion database connection
+   * @param session_hash hash to identify refresh session
+   * @param oldcoin_index index of the coin to retrieve
+   * @param melt melt data to fill in
+   * @return #GNUNET_OK on success
+   *         #GNUNET_SYSERR on internal error
+   */
+  int
+  (*get_refresh_melt) (void *cls,
+                       struct TALER_MINTDB_Session *sesssion,
+                       const struct GNUNET_HashCode *session_hash,
+                       uint16_t oldcoin_index,
+                       struct RefreshMelt *melt);
+
+
+  /**
+   * Store in the database which coin(s) we want to create
+   * in a given refresh operation.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param sesssion database connection
+   * @param session_hash hash to identify refresh session
+   * @param num_newcoins number of coins to generate, size of the @a denom_pubs array
+   * @param denom_pubs array denominations of the coins to create
+   * @return #GNUNET_OK on success
+   *         #GNUNET_SYSERR on internal error
+   */
+  int
+  (*insert_refresh_order) (void *cls,
+                           struct TALER_MINTDB_Session *sesssion,
+                           const struct GNUNET_HashCode *session_hash,
+                           uint16_t num_newcoins,
+                           const struct TALER_DenominationPublicKey *denom_pubs);
+
+
+  /**
+   * Lookup in the database for the @a num_newcoins coins that we want to
+   * create in the given refresh operation.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param sesssion database connection
+   * @param session_hash hash to identify refresh session
+   * @param num_newcoins size of the @a denom_pubs array
+   * @param denom_pubs[OUT] where to write @a num_newcoins denomination keys
+   * @return #GNUNET_OK on success
+   *         #GNUNET_SYSERR on internal error
+   */
+  int
+  (*get_refresh_order) (void *cls,
+                        struct TALER_MINTDB_Session *sesssion,
+                        const struct GNUNET_HashCode *session_hash,
+                        uint16_t num_newcoins,
+                        struct TALER_DenominationPublicKey *denom_pubs);
+
+
+  /**
+   * Store information about the commitments of the given index @a i
+   * for the given refresh session in the database.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param sesssion database connection to use
+   * @param session_hash hash to identify refresh session
+   * @param i set index (1st dimension), relating to #TALER_CNC_KAPPA
+   * @param num_newcoins coin index size of the @a commit_coins array
+   * @param commit_coin array of coin commitments to store
+   * @return #GNUNET_OK on success
+   *         #GNUNET_SYSERR on error
+   */
+  int
+  (*insert_refresh_commit_coins) (void *cls,
+                                  struct TALER_MINTDB_Session *sesssion,
+                                  const struct GNUNET_HashCode *session_hash,
+                                  unsigned int i,
+                                  unsigned int num_newcoins,
+                                  const struct RefreshCommitCoin *commit_coins);
+
+
+  /**
+   * Obtain information about the commitment of the
+   * given coin of the given refresh session from the database.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param sesssion database connection to use
+   * @param session_hash hash to identify refresh session
+   * @param i set index (1st dimension)
+   * @param num_coins size of the @a commit_coins array
+   * @param commit_coin[OUT] array of coin commitments to return
+   * @return #GNUNET_OK on success
+   *         #GNUNET_NO if not found
+   *         #GNUNET_SYSERR on error
+   */
+  int
+  (*get_refresh_commit_coins) (void *cls,
+                               struct TALER_MINTDB_Session *sesssion,
+                               const struct GNUNET_HashCode *session_hash,
+                               unsigned int i,
+                               unsigned int num_coins,
+                               struct RefreshCommitCoin *commit_coins);
+
+
+  /**
+   * Store the commitment to the given (encrypted) refresh link data
+   * for the given refresh session.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param sesssion database connection to use
+   * @param session_hash hash to identify refresh session
+   * @param i set index (1st dimension), relating to #TALER_CNC_KAPPA
+   * @param num_links size of the @a commit_link array
+   * @param commit_links array of link information to store
+   * @return #GNUNET_SYSERR on internal error, #GNUNET_OK on success
+   */
+  int
+  (*insert_refresh_commit_links) (void *cls,
+                                  struct TALER_MINTDB_Session *sesssion,
+                                  const struct GNUNET_HashCode *session_hash,
+                                  unsigned int i,
+                                  unsigned int num_links,
+                                  const struct RefreshCommitLink *commit_links);
+
+  /**
+   * Obtain the commited (encrypted) refresh link data
+   * for the given refresh session.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param sesssion database connection to use
+   * @param session_hash hash to identify refresh session
+   * @param i set index (1st dimension)
+   * @param num_links size of the @links array to return
+   * @param links[OUT] array link information to return
+   * @return #GNUNET_SYSERR on internal error,
+   *         #GNUNET_NO if commitment was not found
+   *         #GNUNET_OK on success
+   */
+  int
+  (*get_refresh_commit_links) (void *cls,
+                               struct TALER_MINTDB_Session *sesssion,
+                               const struct GNUNET_HashCode *session_hash,
+                               unsigned int i,
+                               unsigned int num_links,
+                               struct RefreshCommitLink *links);
+
+
+  /**
+   * Insert signature of a new coin generated during refresh into
+   * the database indexed by the refresh session and the index
+   * of the coin.  This data is later used should an old coin
+   * be used to try to obtain the private keys during "/refresh/link".
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param sesssion database connection
+   * @param session_hash hash to identify refresh session
+   * @param newcoin_index coin index
+   * @param ev_sig coin signature
+   * @return #GNUNET_OK on success
+   */
+  int
+  (*insert_refresh_collectable) (void *cls,
+                                 struct TALER_MINTDB_Session *sesssion,
+                                 const struct GNUNET_HashCode *session_hash,
+                                 uint16_t newcoin_index,
+                                 const struct TALER_DenominationSignature *ev_sig);
+
+
+  /**
+   * Obtain the link data of a coin, that is the encrypted link
+   * information, the denomination keys and the signatures.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param sesssion database connection
+   * @param coin_pub public key to use to retrieve linkage data
+   * @return all known link data for the coin
+   */
+  struct LinkDataList *
+  (*get_link_data_list) (void *cls,
+                         struct TALER_MINTDB_Session *sesssion,
+                         const union TALER_CoinSpendPublicKeyP *coin_pub);
+
+
+  /**
+   * Free memory of the link data list.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param ldl link data list to release
+   */
+  void
+  (*free_link_data_list) (void *cls,
+                          struct LinkDataList *ldl);
+
+
+  /**
+   * Obtain shared secret and transfer public key from the public key of
+   * the coin.  This information and the link information returned by
+   * #TALER_db_get_link() enable the owner of an old coin to determine
+   * the private keys of the new coins after the melt.
+   *
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param sesssion database connection
+   * @param coin_pub public key of the coin
+   * @param transfer_pub[OUT] public transfer key
+   * @param shared_secret_enc[OUT] set to shared secret
+   * @return #GNUNET_OK on success,
+   *         #GNUNET_NO on failure (not found)
+   *         #GNUNET_SYSERR on internal failure (database issue)
+   */
+  int
+  (*get_transfer) (void *cls,
+                   struct TALER_MINTDB_Session *sesssion,
+                   const union TALER_CoinSpendPublicKeyP *coin_pub,
+                   struct TALER_TransferPublicKeyP *transfer_pub,
+                   struct TALER_EncryptedLinkSecretP *shared_secret_enc);
+
+
+  /**
+   * Test if the given /lock request is known to us.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param sesssion database connection
+   * @param lock lock operation
+   * @return #GNUNET_YES if known,
+   *         #GNUENT_NO if not,
+   *         #GNUNET_SYSERR on internal error
+   */
+  int
+  (*have_lock) (void *cls,
+                struct TALER_MINTDB_Session *sesssion,
+                const struct Lock *lock);
+
+
+  /**
+   * Store the given /lock request in the database.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param sesssion database connection
+   * @param lock lock operation
+   * @return #GNUNET_OK on success
+   *         #GNUNET_SYSERR on internal error
+   */
+  int
+  (*insert_lock) (void *cls,
+                  struct TALER_MINTDB_Session *sesssion,
+                  const struct Lock *lock);
+
+
+  /**
+   * Compile a list of all (historic) transactions performed
+   * with the given coin (/refresh/melt and /deposit operations).
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param sesssion database connection
+   * @param coin_pub coin to investigate
+   * @return list of transactions, NULL if coin is fresh
+   */
+  struct TALER_MINT_DB_TransactionList *
+  (*get_coin_transactions) (void *cls,
+                            struct TALER_MINTDB_Session *sesssion,
+                            const union TALER_CoinSpendPublicKeyP *coin_pub);
+
+
+  /**
+   * Free linked list of transactions.
+   *
+   * @param cls the @e cls of this struct with the plugin-specific state
+   * @param list list to free
+   */
+  void
+  (*free_coin_transaction_list) (void *cls,
+                                 struct TALER_MINT_DB_TransactionList *list);
+
+
+};
+
+
+#endif /* _NEURO_MINT_DB_H */
diff --git a/src/include/taler_pq_lib.h b/src/include/taler_pq_lib.h
new file mode 100644
index 000000000..3cfd27f91
--- /dev/null
+++ b/src/include/taler_pq_lib.h
@@ -0,0 +1,188 @@
+/*
+  This file is part of TALER
+  Copyright (C) 2014 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 pq/taler_pq_lib.h
+ * @brief helper functions for DB interactions
+ * @author Sree Harsha Totakura <sreeharsha@totakura.in>
+ * @author Florian Dold
+ * @author Christian Grothoff
+ */
+#ifndef TALER_PQ_LIB_H_
+#define TALER_PQ_LIB_H_
+
+#include <libpq-fe.h>
+#include "taler_util.h"
+
+/**
+ * Description of a DB query parameter.
+ */
+struct TALER_PQ_QueryParam
+{
+  /**
+   * Data or NULL
+   */
+  const void *data;
+
+  /**
+   * Size of @e data
+   */
+  size_t size;
+
+  /**
+   * Non-null if this is not the last parameter.
+   * This allows for null as sentinal value.
+   */
+  int more;
+};
+
+/**
+ * End of query parameter specification.
+ */
+#define TALER_PQ_QUERY_PARAM_END { NULL, 0, 0 }
+
+/**
+ * Generate fixed-size query parameter with size given explicitly.
+ *
+ * @param x pointer to the query parameter to pass
+ * @param s number of bytes of @a x to use for the query
+ */
+#define TALER_PQ_QUERY_PARAM_PTR_SIZED(x, s) { (x), (s), 1 }
+
+/**
+ * Generate fixed-size query parameter with size determined
+ * by variable type.
+ *
+ * @param x pointer to the query parameter to pass.
+ */
+#define TALER_PQ_QUERY_PARAM_PTR(x) TALER_PQ_QUERY_PARAM_PTR_SIZED(x, sizeof (*(x)))
+
+
+/**
+ * Description of a DB result cell.
+ */
+struct TALER_PQ_ResultSpec
+{
+  /**
+   * Destination for the data.
+   */
+  void *dst;
+
+  /**
+   * Allowed size for the data, 0 for variable-size
+   * (in this case, the type of @e dst is a `void **`
+   * and we need to allocate a buffer of the right size).
+   */
+  size_t dst_size;
+
+  /**
+   * Field name of the desired result.
+   */
+  char *fname;
+
+  /**
+   * Actual size of the result.
+   */
+  size_t *result_size;
+
+};
+
+
+/**
+ * End of result parameter specification.
+ */
+#define TALER_PQ_RESULT_SPEC_END { NULL, 0, NULL, NULL }
+
+/**
+ * We expect a fixed-size result, with size given explicitly
+ *
+ * @param name name of the field in the table
+ * @param dst point to where to store the result
+ * @param s number of bytes we should use in @a dst
+ */
+#define TALER_PQ_RESULT_SPEC_SIZED(name, dst, s) { (void *) (dst), (s), (name), NULL }
+
+/**
+ * We expect a fixed-size result, with size determined by the type of `* dst`
+ *
+ * @param name name of the field in the table
+ * @param dst point to where to store the result, type fits expected result size
+ */
+#define TALER_PQ_RESULT_SPEC(name, dst) TALER_PQ_RESULT_SPEC_SIZED(name, dst, sizeof (*(dst)))
+
+/**
+ * Variable-size result expected.
+ *
+ * @param name name of the field in the table
+ * @param dst where to store the result (of type void **), to be allocated
+ * @param sptr pointer to a `size_t` for where to store the size of @a dst
+ */
+#define TALER_PQ_RESULT_SPEC_VAR(name, dst, sptr) { (void *) (dst), 0, (name), sptr }
+
+
+/**
+ * Execute a prepared statement.
+ */
+PGresult *
+TALER_PQ_exec_prepared (PGconn *db_conn,
+                        const char *name,
+                        const struct TALER_PQ_QueryParam *params);
+
+
+/**
+ * Extract results from a query result according to the given specification.
+ * If colums are NULL, the destination is not modified, and GNUNET_NO
+ * is returned.
+ *
+ * @return
+ *   #GNUNET_YES if all results could be extracted
+ *   #GNUNET_NO if at least one result was NULL
+ *   #GNUNET_SYSERR if a result was invalid (non-existing field)
+ */
+int
+TALER_PQ_extract_result (PGresult *result,
+                         struct TALER_PQ_ResultSpec *rs,
+                         int row);
+
+
+int
+TALER_PQ_field_isnull (PGresult *result,
+                       int row,
+                       const char *fname);
+
+
+int
+TALER_PQ_extract_amount_nbo (PGresult *result,
+                             int row,
+                             const char *val_name,
+                             const char *frac_name,
+                             const char *curr_name,
+                             struct TALER_AmountNBO *r_amount_nbo);
+
+
+int
+TALER_PQ_extract_amount (PGresult *result,
+                         int row,
+                         const char *val_name,
+                         const char *frac_name,
+                         const char *curr_name,
+                         struct TALER_Amount *r_amount);
+
+
+
+
+#endif  /* TALER_PQ_LIB_H_ */
+
+/* end of db/taler_pq_lib.h */
diff --git a/src/include/taler_signatures.h b/src/include/taler_signatures.h
index 007a309f3..41b694d09 100644
--- a/src/include/taler_signatures.h
+++ b/src/include/taler_signatures.h
@@ -32,61 +32,61 @@
 
 /**
  * Cut-and-choose size for refreshing.  Client looses the gamble (of
- * unaccountable transfers) with probability 1/KAPPA.  Refresh cost
- * increases linearly with KAPPA, and 3 is sufficient up to a
+ * unaccountable transfers) with probability 1/TALER_CNC_KAPPA.  Refresh cost
+ * increases linearly with TALER_CNC_KAPPA, and 3 is sufficient up to a
  * income/sales tax of 66% of total transaction value.  As there is
  * no good reason to change this security parameter, we declare it
  * fixed and part of the protocol.
  */
-#define KAPPA 3
+#define TALER_CNC_KAPPA 3
 
 
 /**
  * Purpose for signing public keys signed
  * by the mint master key.
  */
-#define TALER_SIGNATURE_MASTER_SIGNKEY 1
+#define TALER_SIGNATURE_MINT_SIGNING_KEY_VALIDITY 1
 
 /**
  * Purpose for denomination keys signed
  * by the mint master key.
  */
-#define TALER_SIGNATURE_MASTER_DENOM 2
+#define TALER_SIGNATURE_MINT_DENOMINATION_KEY_VALIDITY 2
 
 /**
  * Purpose for the state of a reserve,
  * signed by the mint's signing key.
  */
-#define TALER_SIGNATURE_RESERVE_STATUS 3
+#define TALER_SIGNATURE_MINT_RESERVE_STATUS 3
 
 /**
  * Signature where the reserve key
  * confirms a withdraw request.
  */
-#define TALER_SIGNATURE_WITHDRAW 4
+#define TALER_SIGNATURE_RESERVE_WITHDRAW_REQUEST 4
 
 /**
  * Signature using a coin key confirming the melting of
  * a coin.
  */
-#define TALER_SIGNATURE_REFRESH_MELT_COIN 5
+#define TALER_SIGNATURE_COIN_MELT 5
 
 /**
  * Signature where the mint (current signing key)
  * confirms the no-reveal index for cut-and-choose and
  * the validity of the melted coins.
  */
-#define TALER_SIGNATURE_REFRESH_MELT_RESPONSE 6
+#define TALER_SIGNATURE_MINT_MELT_RESPONSE 6
 
 /**
  * Signature where the Mint confirms a deposit request.
  */
-#define TALER_SIGNATURE_MINT_DEPOSIT 7
+#define TALER_SIGNATURE_COIN_DEPOSIT 7
 
 /**
  * Signature where the Mint confirms the full /keys response set.
  */
-#define TALER_SIGNATURE_KEYS_SET 8
+#define TALER_SIGNATURE_MINT_KEY_SET 8
 
 
 /***********************/
@@ -104,11 +104,14 @@
 
 /**
  * Signature made by the wallet of a user to confirm a deposit permission
+ * FIXME: this is #TALER_SIGNATURE_COIN_DEPOSIT already!
  */
 #define TALER_SIGNATURE_WALLET_DEPOSIT 201
 
 /**
- * Signature made by the wallet of a user to confirm a incremental deposit permission
+ * Signature made by the wallet of a user to confirm a incremental
+ * deposit permission.
+ * FIXME: this MIGHT also be #TALER_SIGNATURE_COIN_DEPOSIT already!
  */
 #define TALER_SIGNATURE_INCREMENTAL_WALLET_DEPOSIT 202
 
@@ -120,11 +123,11 @@ GNUNET_NETWORK_STRUCT_BEGIN
  * Format used for to generate the signature on a request to withdraw
  * coins from a reserve.
  */
-struct TALER_WithdrawRequest
+struct TALER_WithdrawRequestPS
 {
 
   /**
-   * Purpose must be #TALER_SIGNATURE_WITHDRAW.
+   * Purpose must be #TALER_SIGNATURE_RESERVE_WITHDRAW_REQUEST.
    */
   struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
 
@@ -132,7 +135,7 @@ struct TALER_WithdrawRequest
    * Reserve public key (which reserve to withdraw from).  This is
    * the public key which must match the signature.
    */
-  struct TALER_ReservePublicKey reserve_pub;
+  struct TALER_ReservePublicKeyP reserve_pub;
 
   /**
    * Value of the coin being minted (matching the denomination key)
@@ -159,7 +162,7 @@ struct TALER_WithdrawRequest
  * Format used to generate the signature on a request to deposit
  * a coin into the account of a merchant.
  */
-struct TALER_DepositRequest
+struct TALER_DepositRequestPS
 {
   /**
    * Purpose must be #TALER_SIGNATURE_WALLET_DEPOSIT
@@ -192,7 +195,7 @@ struct TALER_DepositRequest
   /**
    * The coin's public key.
    */
-  struct TALER_CoinSpendPublicKey coin_pub;
+  union TALER_CoinSpendPublicKeyP coin_pub;
 
 };
 
@@ -201,10 +204,10 @@ struct TALER_DepositRequest
  * Format used to generate the signature on a confirmation
  * from the mint that a deposit request succeeded.
  */
-struct TALER_DepositConfirmation
+struct TALER_DepositConfirmationPS
 {
   /**
-   * Purpose must be #TALER_SIGNATURE_MINT_DEPOSIT
+   * Purpose must be #TALER_SIGNATURE_COIN_DEPOSIT
    */
   struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
 
@@ -235,12 +238,12 @@ struct TALER_DepositConfirmation
   /**
    * The coin's public key.
    */
-  struct TALER_CoinSpendPublicKey coin_pub;
+  union TALER_CoinSpendPublicKeyP coin_pub;
 
   /**
    * The Merchant's public key.
    */
-  struct TALER_MerchantPublicKey merchant;
+  struct TALER_MerchantPublicKeyP merchant;
 
 };
 
@@ -249,10 +252,10 @@ struct TALER_DepositConfirmation
  * Message signed by a coin to indicate that the coin should
  * be melted.
  */
-struct RefreshMeltCoinSignature
+struct TALER_RefreshMeltCoinAffirmationPS
 {
   /**
-   * Purpose is #TALER_SIGNATURE_REFRESH_MELT_COIN.
+   * Purpose is #TALER_SIGNATURE_COIN_MELT.
    */
   struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
 
@@ -277,7 +280,7 @@ struct RefreshMeltCoinSignature
   /**
    * The coin's public key.
    */
-  struct TALER_CoinSpendPublicKey coin_pub;
+  union TALER_CoinSpendPublicKeyP coin_pub;
 };
 
 
@@ -287,10 +290,10 @@ struct RefreshMeltCoinSignature
  * coins were successfully melted.  This also commits the mint to a
  * particular index to not be revealed during the refresh.
  */
-struct RefreshMeltResponseSignatureBody
+struct TALER_RefreshMeltConfirmationPS
 {
   /**
-   * Purpose is #TALER_SIGNATURE_REFRESH_MELT_RESPONSE.
+   * Purpose is #TALER_SIGNATURE_MINT_MELT_RESPONSE.
    */
   struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
 
@@ -311,15 +314,15 @@ struct RefreshMeltResponseSignatureBody
  * to sign mint messages other than coins, i.e. to confirm that a
  * deposit was successful or that a refresh was accepted.
  */
-struct TALER_MINT_SignKeyIssue
+struct TALER_MintSigningKeyValidityPS
 {
   /**
    * Signature over the signing key (by the master key of the mint).
    */
-  struct TALER_MasterSignature signature;
+  struct TALER_MasterSignatureP signature;
 
   /**
-   * Purpose is #TALER_SIGNATURE_MASTER_SIGNKEY.
+   * Purpose is #TALER_SIGNATURE_MINT_SIGNING_KEY_VALIDITY.
    */
   struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
 
@@ -327,7 +330,7 @@ struct TALER_MINT_SignKeyIssue
    * Master public key of the mint corresponding to @e signature.
    * This is the long-term offline master key of the mint.
    */
-  struct TALER_MasterPublicKey master_pub;
+  struct TALER_MasterPublicKeyP master_public_key;
 
   /**
    * When does this signing key begin to be valid?
@@ -346,7 +349,7 @@ struct TALER_MINT_SignKeyIssue
    * The public online signing key that the mint will use
    * between @e start and @e expire.
    */
-  struct TALER_MintPublicKey signkey_pub;
+  struct TALER_MintPublicKeyP signkey_pub;
 };
 
 
@@ -355,11 +358,11 @@ struct TALER_MINT_SignKeyIssue
  * to detect cheating mints that give out different sets to
  * different users.
  */
-struct TALER_MINT_KeySetSignature
+struct TALER_MintKeySetPS
 {
 
   /**
-   * Purpose is #TALER_SIGNATURE_KEYS_SET
+   * Purpose is #TALER_SIGNATURE_MINT_KEY_SET
    */
   struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
 
@@ -379,16 +382,16 @@ struct TALER_MINT_KeySetSignature
  * Information about a denomination key. Denomination keys
  * are used to sign coins of a certain value into existence.
  */
-struct TALER_MINT_DenomKeyIssue
+struct TALER_DenominationKeyValidityPS
 {
   /**
    * Signature over this struct to affirm the validity
    * of the key.
    */
-  struct TALER_MasterSignature signature;
+  struct TALER_MasterSignatureP signature;
 
   /**
-   * Purpose is #TALER_SIGNATURE_MASTER_DENOM.
+   * Purpose is #TALER_SIGNATURE_MINT_DENOMINATION_KEY_VALIDITY.
    */
   struct GNUNET_CRYPTO_EccSignaturePurpose purpose;
 
@@ -396,7 +399,7 @@ struct TALER_MINT_DenomKeyIssue
    * The long-term offline master key of the mint that was
    * used to create @e signature.
    */
-  struct TALER_MasterPublicKey master;
+  struct TALER_MasterPublicKeyP master;
 
   /**
    * Start time of the validity period for this key.
diff --git a/src/include/taler_util.h b/src/include/taler_util.h
index e46583989..b92f22170 100644
--- a/src/include/taler_util.h
+++ b/src/include/taler_util.h
@@ -29,13 +29,13 @@
 
 
 /* Define logging functions */
-#define LOG_DEBUG(...)                                  \
+#define TALER_LOG_DEBUG(...)                                  \
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, __VA_ARGS__)
 
-#define LOG_WARNING(...)                                \
+#define TALER_LOG_WARNING(...)                                \
   GNUNET_log (GNUNET_ERROR_TYPE_WARNING, __VA_ARGS__)
 
-#define LOG_ERROR(...)                                  \
+#define TALER_LOG_ERROR(...)                                  \
   GNUNET_log (GNUNET_ERROR_TYPE_ERROR, __VA_ARGS__)
 
 
@@ -49,7 +49,7 @@
 #define TALER_assert_as(EXP, reason)                           \
   do {                                                          \
     if (EXP) break;                                             \
-    LOG_ERROR("%s at %s:%d\n", reason, __FILE__, __LINE__);       \
+    TALER_LOG_ERROR("%s at %s:%d\n", reason, __FILE__, __LINE__);       \
     abort();                                                    \
   } while(0)
 
@@ -59,11 +59,11 @@
  * a failure of the command 'cmd' with the message given
  * by gcry_strerror(rc).
  */
-#define LOG_GCRY_ERROR(cmd, rc) do { LOG_ERROR("`%s' failed at %s:%d with error: %s\n", cmd, __FILE__, __LINE__, gcry_strerror(rc)); } while(0)
+#define TALER_LOG_GCRY_ERROR(cmd, rc) do { TALER_LOG_ERROR("`%s' failed at %s:%d with error: %s\n", cmd, __FILE__, __LINE__, gcry_strerror(rc)); } while(0)
 
 
 #define TALER_gcry_ok(cmd) \
-  do {int rc; rc = cmd; if (!rc) break; LOG_ERROR("A Gcrypt call failed at %s:%d with error: %s\n", __FILE__, __LINE__, gcry_strerror(rc)); abort(); } while (0)
+  do {int rc; rc = cmd; if (!rc) break; TALER_LOG_ERROR("A Gcrypt call failed at %s:%d with error: %s\n", __FILE__, __LINE__, gcry_strerror(rc)); abort(); } while (0)
 
 
 /**
@@ -108,7 +108,7 @@ TALER_config_get_denom (struct GNUNET_CONFIGURATION_Handle *cfg,
  * @return a pointer to the dir path (to be freed by the caller)
  */
 char *
-TALER_OS_installation_get_path (enum GNUNET_OS_InstallationPathKind dirkind);
+TALER_os_installation_get_path (enum GNUNET_OS_InstallationPathKind dirkind);
 
 
 #endif