5136: fix multiple invocations of /keys callback.

Basically, we allow such a callback to be invoked only once.
Subsequent invocations (due to keys updates / whatever) cause
the callback to simply return in a do-nothing fashion.

Also: adding a /wire CMD - that uses /keys - after serilized
keys have been loaded.

src/exchange-lib/exchange_api_handle.c

@@ -2,18 +2,21 @@
   This file is part of TALER
   Copyright (C) 2014-2018 GNUnet e.V.
 
-  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 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.
+  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, see
+  You should have received a copy of the GNU General Public
+  License along with TALER; see the file COPYING.  If not, see
   <http://www.gnu.org/licenses/>
 */
+
 /**
  * @file exchange-lib/exchange_api_handle.c
  * @brief Implementation of the "handle" component of the exchange's HTTP API
@@ -1372,21 +1375,25 @@ TALER_EXCHANGE_serialize_data (struct TALER_EXCHANGE_Handle *exchange)
 
 /**
  * Initialise a connection to the exchange. Will connect to the
- * exchange and obtain information about the exchange's master public
- * key and the exchange's auditor.  The respective information will
- * be passed to the @a cert_cb once available, and all future
- * interactions with the exchange will be checked to be signed
- * (where appropriate) by the respective master key.
+ * exchange and obtain information about the exchange's master
+ * public key and the exchange's auditor.
+ * The respective information will be passed to the @a cert_cb
+ * once available, and all future interactions with the exchange
+ * will be checked to be signed (where appropriate) by the
+ * respective master key.
  *
  * @param ctx the context
  * @param url HTTP base URL for the exchange
- * @param cert_cb function to call with the exchange's certification information
+ * @param cert_cb function to call with the exchange's
+ *        certification information
  * @param cert_cb_cls closure for @a cert_cb
- * @param ... list of additional arguments, terminated by #TALER_EXCHANGE_OPTION_END.
+ * @param ... list of additional arguments,
+ *        terminated by #TALER_EXCHANGE_OPTION_END.
  * @return the exchange handle; NULL upon error
  */
 struct TALER_EXCHANGE_Handle *
-TALER_EXCHANGE_connect (struct GNUNET_CURL_Context *ctx,
+TALER_EXCHANGE_connect
+  (struct GNUNET_CURL_Context *ctx,
    const char *url,
    TALER_EXCHANGE_CertificationCallback cert_cb,
    void *cert_cb_cls,

src/exchange-lib/exchange_api_wire.c

@@ -213,6 +213,7 @@ handle_wire_finished (void *cls,
   enum TALER_ErrorCode ec;
   const json_t *j = response;
 
+  TALER_LOG_DEBUG ("Checking raw /wire response\n");
   wh->job = NULL;
   ec = TALER_EC_NONE;
   switch (response_code)

src/exchange-lib/testing_api_cmd_batch.c

@@ -60,6 +60,7 @@ batch_run (void *cls,
   struct BatchState *bs = cls;
 
   bs->batch_ip++;
+  if (NULL != bs->batch[bs->batch_ip].label)
     TALER_LOG_DEBUG ("Running batched command: %s\n",
                      bs->batch[bs->batch_ip].label);
 

src/exchange-lib/testing_api_cmd_serialize_keys.c

@@ -48,6 +48,34 @@ struct SerializeKeysState
 };
 
 
+/**
+ * Internal state for a connect-with-state CMD.
+ */
+struct ConnectWithStateState
+{
+
+  /**
+   * Reference to a CMD that offers a serialized key-state
+   * that will be used in the reconnection.
+   */
+  const char *state_reference;
+
+  /**
+   * If set to GNUNET_YES, then the /keys callback has already
+   * been passed the control to the next CMD.  This is necessary
+   * because it is not uncommon that the /keys callback gets
+   * invoked multiple times, and without this flag, we would keep
+   * going "next" CMD upon every invocation (causing impredictable
+   * behaviour as for the instruction pointer.)
+   */
+  unsigned int consumed;
+
+  /**
+   * Interpreter state.
+   */
+  struct TALER_TESTING_Interpreter *is;
+};
+
 /**
  * Run the command.
  *
@@ -91,6 +119,7 @@ serialize_keys_cleanup (void *cls,
     json_decref (sks->keys);   
   }
 
+  GNUNET_free ((char *) sks->exchange_url);
   GNUNET_free (sks);
 }
 
@@ -140,15 +169,23 @@ cb (void *cls,
     const struct TALER_EXCHANGE_Keys *keys,
     enum TALER_EXCHANGE_VersionCompatibility compat)
 {
-  struct TALER_TESTING_Interpreter *is = cls;
+  struct ConnectWithStateState *cwss = cls;
 
+  if (GNUNET_YES == cwss->consumed)
+  {
+    TALER_LOG_DEBUG ("Reconnection /keys 'cb' invoked already,"
+                     " nothing to do\n"); 
+    return;
+  }
+
+  cwss->consumed = GNUNET_YES;
   if (NULL == keys)
-    TALER_TESTING_interpreter_fail (is);
+    TALER_TESTING_interpreter_fail (cwss->is);
   
-  TALER_TESTING_interpreter_next (is);
+  TALER_LOG_DEBUG ("reconnect next CMD\n");
+  TALER_TESTING_interpreter_next (cwss->is);
 }
 
-
 /**
  * Run the command.
  *
@@ -161,13 +198,14 @@ connect_with_state_run (void *cls,
                         const struct TALER_TESTING_Command *cmd,
                         struct TALER_TESTING_Interpreter *is)
 {
+  struct ConnectWithStateState *cwss = cls;
   const struct TALER_TESTING_Command *state_cmd;
   const json_t *serialized_keys;
-  const char *state_reference = cls;
   const char *exchange_url;
 
+  cwss->is = is;
   state_cmd = TALER_TESTING_interpreter_lookup_command
-    (is, state_reference);
+    (is, cwss->state_reference);
 
   /* Command providing serialized keys not found.  */
   if (NULL == state_cmd)
@@ -197,7 +235,7 @@ connect_with_state_run (void *cls,
     (is->ctx,
      exchange_url,
      cb,
-     is,
+     cwss,
      TALER_EXCHANGE_OPTION_DATA,
      serialized_keys,
      TALER_EXCHANGE_OPTION_END);
@@ -216,7 +254,9 @@ connect_with_state_cleanup
   (void *cls,
    const struct TALER_TESTING_Command *cmd)
 {
-  return;
+  struct ConnectWithStateState *cwss = cls;
+
+  GNUNET_free (cwss);
 }
 
 /**
@@ -244,7 +284,6 @@ TALER_TESTING_cmd_serialize_keys (const char *label)
   return cmd;
 }
 
-
 /**
  * Make a connect-with-state CMD.  This command
  * will use a serialized key state to reconnect
@@ -259,8 +298,14 @@ struct TALER_TESTING_Command
 TALER_TESTING_cmd_connect_with_state (const char *label,
                                       const char *state_reference)
 {
+  struct ConnectWithStateState *cwss;
+
+  cwss = GNUNET_new (struct ConnectWithStateState);
+  cwss->state_reference = state_reference;
+  cwss->consumed = GNUNET_NO;
+
   struct TALER_TESTING_Command cmd = {
-    .cls = (char *) state_reference,
+    .cls = cwss,
     .label = label,
     .run = connect_with_state_run, 
     .cleanup = connect_with_state_cleanup

src/exchange-lib/testing_api_cmd_wire.c

@@ -94,6 +94,7 @@ wire_cb (void *cls,
     &ws->is->commands[ws->is->ip];
   struct TALER_Amount expected_fee;
 
+  TALER_LOG_DEBUG ("Checking parsed /wire response\n");
   ws->wh = NULL;
   if (ws->expected_response_code != http_status)
   {
@@ -137,6 +138,8 @@ wire_cb (void *cls,
           }
         }
       }
+      TALER_LOG_DEBUG ("Freeing method '%s'\n",
+                       method);
       GNUNET_free (method);
     }
     if (GNUNET_OK != ws->method_found)
@@ -148,6 +151,7 @@ wire_cb (void *cls,
       return;
     }
   }
+
   TALER_TESTING_interpreter_next (ws->is);
 }
 

src/exchange-lib/testing_api_loop.c

@@ -237,6 +237,8 @@ struct TALER_TESTING_Command
 TALER_TESTING_cmd_end (void)
 {
   static struct TALER_TESTING_Command cmd;
+  cmd.label = NULL;
+
   return cmd;
 }
 
@@ -269,13 +271,18 @@ interpreter_run (void *cls)
 
   if (NULL == cmd->label)
   {
+
+    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                "Running command END\n");
     is->result = GNUNET_OK;
     GNUNET_SCHEDULER_shutdown ();
     return;
   }
+
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
               "Running command `%s'\n",
               cmd->label);
+
   cmd->run (cmd->cls,
             cmd,
             is);
@@ -293,10 +300,16 @@ do_shutdown (void *cls)
 {
   struct TALER_TESTING_Interpreter *is = cls;
   struct TALER_TESTING_Command *cmd;
+  const char *label;
+
+  label = is->commands[is->ip].label;
+  if (NULL == label)
+    label = "END";
 
   GNUNET_log (GNUNET_ERROR_TYPE_INFO,
               "Executing shutdown at `%s'\n",
-              is->commands[is->ip].label);
+              label);
+
   for (unsigned int j=0;NULL != (cmd = &is->commands[j])->label;j++)
     cmd->cleanup (cmd->cls,
                   cmd);