address 'global_ret' simplification TODO

1 files changed, 69 insertions, 47 deletions

diff --git a/src/exchange/taler-exchange-aggregator.c b/src/exchange/taler-exchange-aggregator.c
index cfc11a5f9..96922eff2 100644
--- a/src/exchange/taler-exchange-aggregator.c
+++ b/src/exchange/taler-exchange-aggregator.c
@@ -20,7 +20,6 @@
  * @author Christian Grothoff
  *
  * TODO:
- * - simplify global_ret: make it a global!
  * - handle shutdown more nicely (call 'cancel' method on wire transfers)
  */
 #include "platform.h"
@@ -68,6 +67,12 @@ static struct TALER_WIRE_Plugin *wire_plugin;
 static struct GNUNET_SCHEDULER_Task *task;
 
 /**
+ * Value to return from main(). #GNUNET_OK on success, #GNUNET_SYSERR
+ * on serious errors.
+ */
+static int global_ret;
+
+/**
  * #GNUNET_YES if we are in test mode and are using temporary tables.
  */
 static int test_mode;
@@ -85,6 +90,25 @@ static unsigned int aggregation_limit = TALER_EXCHANGEDB_MATCHING_DEPOSITS_LIMIT
 
 
 /**
+ * We're being aborted with CTRL-C (or SIGTERM). Shut down.
+ *
+ * @param cls closure
+ * @param tc scheduler context
+ */
+static void
+shutdown_task (void *cls,
+               const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+  if (NULL != task)
+  {
+    GNUNET_SCHEDULER_cancel (task);
+    task = NULL;
+  }
+  /* FIXME: other shutdown stuff here! */
+}
+
+
+/**
  * Load configuration parameters for the exchange
  * server into the corresponding global variables.
  *
@@ -217,11 +241,6 @@ struct AggregationUnit
   unsigned long long *additional_rows;
 
   /**
-   * Pointer to global return value. Closure for #run().
-   */
-  int *global_ret;
-
-  /**
    * Offset specifying how many #additional_rows are in use.
    */
   unsigned int rows_offset;
@@ -314,7 +333,6 @@ deposit_cb (void *cls,
 }
 
 
-
 /**
  * Function called with details about another deposit we
  * can aggregate into an existing aggregation unit.
@@ -433,14 +451,13 @@ prepare_cb (void *cls,
  * Main work function that queries the DB and aggregates transactions
  * into larger wire transfers.
  *
- * @param cls pointer to an `int` which we will return from main()
+ * @param cls NULL
  * @param tc scheduler context
  */
 static void
 run_aggregation (void *cls,
                  const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
-  int *global_ret = cls;
   struct TALER_EXCHANGEDB_Session *session;
   struct AggregationUnit *au;
   unsigned int i;
@@ -453,7 +470,7 @@ run_aggregation (void *cls,
   {
     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                 "Failed to obtain database session!\n");
-    *global_ret = GNUNET_SYSERR;
+    global_ret = GNUNET_SYSERR;
     return;
   }
   if (GNUNET_OK !=
@@ -462,7 +479,7 @@ run_aggregation (void *cls,
   {
     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                 "Failed to start database transaction!\n");
-    *global_ret = GNUNET_SYSERR;
+    global_ret = GNUNET_SYSERR;
     return;
   }
   au = GNUNET_new (struct AggregationUnit);
@@ -482,7 +499,7 @@ run_aggregation (void *cls,
     {
       GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                   "Failed to execute deposit iteration!\n");
-      *global_ret = GNUNET_SYSERR;
+      global_ret = GNUNET_SYSERR;
       return;
     }
     if (GNUNET_YES == test_mode)
@@ -495,7 +512,7 @@ run_aggregation (void *cls,
       /* nothing to do, sleep for a minute and try again */
       task = GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_MINUTES,
                                            &run_aggregation,
-                                           global_ret);
+                                           NULL);
     }
     return;
   }
@@ -518,7 +535,7 @@ run_aggregation (void *cls,
     GNUNET_free (au);
     db_plugin->rollback (db_plugin->cls,
                          session);
-    *global_ret = GNUNET_SYSERR;
+    global_ret = GNUNET_SYSERR;
     return;
   }
   /* Round to the unit supported by the wire transfer method */
@@ -541,7 +558,7 @@ run_aggregation (void *cls,
     {
       GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                   "Failed to start database transaction!\n");
-      *global_ret = GNUNET_SYSERR;
+      global_ret = GNUNET_SYSERR;
       GNUNET_free_non_null (au->additional_rows);
       if (NULL != au->wire)
         json_decref (au->wire);
@@ -576,10 +593,9 @@ run_aggregation (void *cls,
     GNUNET_free (au);
     /* start again */
     task = GNUNET_SCHEDULER_add_now (&run_aggregation,
-                                     global_ret);
+                                     NULL);
     return;
   }
-  au->global_ret = global_ret;
   au->ph = wire_plugin->prepare_wire_transfer (wire_plugin->cls,
                                                au->wire,
                                                &au->total_amount,
@@ -600,7 +616,7 @@ run_aggregation (void *cls,
     GNUNET_free (au);
     /* start again */
     task = GNUNET_SCHEDULER_add_now (&run_aggregation,
-                                     global_ret);
+                                     NULL);
     return;
   }
   /* otherwise we continue with #prepare_cb(), see below */
@@ -632,7 +648,6 @@ prepare_cb (void *cls,
             size_t buf_size)
 {
   struct AggregationUnit *au = cls;
-  int *global_ret = au->global_ret;
   struct TALER_EXCHANGEDB_Session *session = au->session;
 
   GNUNET_free_non_null (au->additional_rows);
@@ -646,7 +661,7 @@ prepare_cb (void *cls,
                          session);
     /* start again */
     task = GNUNET_SCHEDULER_add_now (&run_aggregation,
-                                     global_ret);
+                                     NULL);
     return;
   }
 
@@ -663,7 +678,7 @@ prepare_cb (void *cls,
                          session);
     /* start again */
     task = GNUNET_SCHEDULER_add_now (&run_aggregation,
-                                     global_ret);
+                                     NULL);
     return;
   }
 
@@ -677,13 +692,13 @@ prepare_cb (void *cls,
                 "Failed to commit database transaction!\n");
     /* try again */
     task = GNUNET_SCHEDULER_add_now (&run_aggregation,
-                                     global_ret);
+                                     NULL);
     return;
   }
 
   /* run alternative task: actually do wire transfer! */
   task = GNUNET_SCHEDULER_add_now (&run_transfers,
-                                   &global_ret);
+                                   NULL);
 }
 
 
@@ -704,12 +719,6 @@ struct WirePrepareData
   struct TALER_WIRE_ExecuteHandle *eh;
 
   /**
-   * Pointer to global return value. Closure for #run().
-   */
-  int *global_ret;
-
-
-  /**
    * Row ID of the transfer.
    */
   unsigned long long row_id;
@@ -730,7 +739,6 @@ wire_confirm_cb (void *cls,
                  const char *emsg)
 {
   struct WirePrepareData *wpd = cls;
-  int *global_ret = wpd->global_ret;
   struct TALER_EXCHANGEDB_Session *session = wpd->session;
 
   wpd->eh = NULL;
@@ -741,7 +749,7 @@ wire_confirm_cb (void *cls,
                 emsg);
     db_plugin->rollback (db_plugin->cls,
                          session);
-    *global_ret = GNUNET_SYSERR;
+    global_ret = GNUNET_SYSERR;
     GNUNET_free (wpd);
     return;
   }
@@ -753,7 +761,7 @@ wire_confirm_cb (void *cls,
     GNUNET_break (0); /* why!? */
     db_plugin->rollback (db_plugin->cls,
                          session);
-    *global_ret = GNUNET_SYSERR;
+    global_ret = GNUNET_SYSERR;
     GNUNET_free (wpd);
     return;
   }
@@ -766,13 +774,13 @@ wire_confirm_cb (void *cls,
                 "Failed to commit database transaction!\n");
     /* try again */
     task = GNUNET_SCHEDULER_add_now (&run_aggregation,
-                                     global_ret);
+                                     NULL);
     return;
   }
   /* continue with #run_transfers(), just to guard
      against the unlikely case that there are more. */
   task = GNUNET_SCHEDULER_add_now (&run_transfers,
-                                   &global_ret);
+                                   NULL);
 
 }
 
@@ -792,7 +800,6 @@ wire_prepare_cb (void *cls,
                  size_t buf_size)
 {
   struct WirePrepareData *wpd = cls;
-  int *global_ret = wpd->global_ret;
 
   wpd->row_id = rowid;
   wpd->eh = wire_plugin->execute_wire_transfer (wire_plugin->cls,
@@ -808,7 +815,7 @@ wire_prepare_cb (void *cls,
     GNUNET_break (0); /* why? how to best recover? */
     db_plugin->rollback (db_plugin->cls,
                          wpd->session);
-    *global_ret = GNUNET_SYSERR;
+    global_ret = GNUNET_SYSERR;
     GNUNET_free (wpd);
     return;
   }
@@ -819,14 +826,13 @@ wire_prepare_cb (void *cls,
  * Execute the wire transfers that we have committed to
  * do.
  *
- * @param cls pointer to an `int` which we will return from main()
+ * @param cls NULL
  * @param tc scheduler context
  */
 static void
 run_transfers (void *cls,
                const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
-  int *global_ret = cls;
   int ret;
   struct WirePrepareData *wpd;
   struct TALER_EXCHANGEDB_Session *session;
@@ -838,7 +844,7 @@ run_transfers (void *cls,
   {
     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                 "Failed to obtain database session!\n");
-    *global_ret = GNUNET_SYSERR;
+    global_ret = GNUNET_SYSERR;
     return;
   }
   if (GNUNET_OK !=
@@ -847,12 +853,11 @@ run_transfers (void *cls,
   {
     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                 "Failed to start database transaction!\n");
-    *global_ret = GNUNET_SYSERR;
+    global_ret = GNUNET_SYSERR;
     return;
   }
   wpd = GNUNET_new (struct WirePrepareData);
   wpd->session = session;
-  wpd->global_ret = global_ret;
   ret = db_plugin->wire_prepare_data_get (db_plugin->cls,
                                           session,
                                           exchange_wireformat,
@@ -863,7 +868,7 @@ run_transfers (void *cls,
     GNUNET_break (0); /* why? how to best recover? */
     db_plugin->rollback (db_plugin->cls,
                          session);
-    *global_ret = GNUNET_SYSERR;
+    global_ret = GNUNET_SYSERR;
     GNUNET_free (wpd);
     return;
   }
@@ -873,7 +878,7 @@ run_transfers (void *cls,
     db_plugin->rollback (db_plugin->cls,
                          session);
     task = GNUNET_SCHEDULER_add_now (&run_aggregation,
-                                     global_ret);
+                                     NULL);
     GNUNET_free (wpd);
     return;
   }
@@ -882,6 +887,24 @@ run_transfers (void *cls,
 
 
 /**
+ * First task.
+ *
+ * @param cls closure, NULL
+ * @param tc scheduler context
+ */
+static void
+run (void *cls,
+     const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+  task = GNUNET_SCHEDULER_add_now (&run_transfers,
+                                   cls);
+  GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL,
+                                &shutdown_task,
+                                cls);
+}
+
+
+/**
  * The main function of the taler-exchange-httpd server ("the exchange").
  *
  * @param argc number of arguments from the command line
@@ -907,7 +930,6 @@ main (int argc,
     GNUNET_GETOPT_OPTION_VERSION (VERSION "-" VCS_VERSION),
     GNUNET_GETOPT_OPTION_END
   };
-  int ret = GNUNET_OK;
 
   GNUNET_assert (GNUNET_OK ==
                  GNUNET_log_setup ("taler-exchange-aggregator",
@@ -929,12 +951,12 @@ main (int argc,
   {
     return 1;
   }
-
-  GNUNET_SCHEDULER_run (&run_transfers, &ret);
+  global_ret = GNUNET_OK;
+  GNUNET_SCHEDULER_run (&run, NULL);
 
   TALER_EXCHANGEDB_plugin_unload (db_plugin);
   TALER_WIRE_plugin_unload (wire_plugin);
-  return (GNUNET_SYSERR == ret) ? 1 : 0;
+  return (GNUNET_SYSERR == global_ret) ? 1 : 0;
 }
 
 /* end of taler-exchange-aggregator.c */