From b46735fbafdea562a0d56e7ea1ce844faadcc192 Mon Sep 17 00:00:00 2001
From: Christian Grothoff <christian@grothoff.org>
Date: Wed, 13 Sep 2017 14:08:11 +0200
Subject: [PATCH] add argument to TALER_EXCHANGE_check_keys_current() to allow
 forcing the download

---
 .gitignore                             |  1 +
 ChangeLog                              |  5 +++++
 src/exchange-lib/exchange_api_handle.c | 13 +++++++++----
 src/include/taler_exchange_service.h   |  4 +++-
 4 files changed, 18 insertions(+), 5 deletions(-)

diff --git a/.gitignore b/.gitignore
index 608d4d651..885594138 100644
--- a/.gitignore
+++ b/.gitignore
@@ -86,3 +86,4 @@ doc/manual/manual.tp
 doc/manual/manual.vr
 contrib/taler-exchange.tag
 doxygen-doc/
+src/exchange-lib/test_exchange_api_keys_cherry_picking
diff --git a/ChangeLog b/ChangeLog
index d8adb7d97..a133921d5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Wed Sep 13 14:06:44 CEST 2017
+	Add argument to TALER_EXCHANGE_check_keys_current()
+	to force download even if /keys are still considered
+	current. -CG
+
 Fri Jul 14 17:38:54 CEST 2017
 	Fix #4751 by not allowing denomination deletion (GC)
 	to cascade into reserve_out table (and tolerating such
diff --git a/src/exchange-lib/exchange_api_handle.c b/src/exchange-lib/exchange_api_handle.c
index 99255e449..91309cc5e 100644
--- a/src/exchange-lib/exchange_api_handle.c
+++ b/src/exchange-lib/exchange_api_handle.c
@@ -770,14 +770,17 @@ request_keys (struct TALER_EXCHANGE_Handle *exchange);
  * not trigger download.
  *
  * @param exchange exchange to check keys for
+ * @param force_download #GNUNET_YES to force download even if /keys is still valid
  * @return until when the response is current, 0 if we are re-downloading
  */
 struct GNUNET_TIME_Absolute
-TALER_EXCHANGE_check_keys_current (struct TALER_EXCHANGE_Handle *exchange)
+TALER_EXCHANGE_check_keys_current (struct TALER_EXCHANGE_Handle *exchange,
+                                   int force_download)
 {
   if (NULL != exchange->kr)
     return GNUNET_TIME_UNIT_ZERO_ABS;
-  if (0 < GNUNET_TIME_absolute_get_remaining (exchange->key_data_expiration).rel_value_us)
+  if ( (GNUNET_NO == force_download) &&
+       (0 < GNUNET_TIME_absolute_get_remaining (exchange->key_data_expiration).rel_value_us) )
     return exchange->key_data_expiration;
   request_keys (exchange);
   return GNUNET_TIME_UNIT_ZERO_ABS;
@@ -1280,7 +1283,8 @@ TALER_EXCHANGE_get_denomination_key_by_hash (const struct TALER_EXCHANGE_Keys *k
 const struct TALER_EXCHANGE_Keys *
 TALER_EXCHANGE_get_keys (struct TALER_EXCHANGE_Handle *exchange)
 {
-  (void) TALER_EXCHANGE_check_keys_current (exchange);
+  (void) TALER_EXCHANGE_check_keys_current (exchange,
+                                            GNUNET_NO);
   return &exchange->key_data;
 }
 
@@ -1295,7 +1299,8 @@ TALER_EXCHANGE_get_keys (struct TALER_EXCHANGE_Handle *exchange)
 json_t *
 TALER_EXCHANGE_get_keys_raw (struct TALER_EXCHANGE_Handle *exchange)
 {
-  (void) TALER_EXCHANGE_check_keys_current (exchange);
+  (void) TALER_EXCHANGE_check_keys_current (exchange,
+                                            GNUNET_NO);
   return json_deep_copy (exchange->key_data_raw);
 }
 
diff --git a/src/include/taler_exchange_service.h b/src/include/taler_exchange_service.h
index d7056b574..814078a02 100644
--- a/src/include/taler_exchange_service.h
+++ b/src/include/taler_exchange_service.h
@@ -367,10 +367,12 @@ TALER_EXCHANGE_get_keys (struct TALER_EXCHANGE_Handle *exchange);
  * not, trigger /keys download.
  *
  * @param exchange exchange to check keys for
+ * @param force_download #GNUNET_YES to force download even if /keys is still valid
  * @return until when the response is current, 0 if we are re-downloading
  */
 struct GNUNET_TIME_Absolute
-TALER_EXCHANGE_check_keys_current (struct TALER_EXCHANGE_Handle *exchange);
+TALER_EXCHANGE_check_keys_current (struct TALER_EXCHANGE_Handle *exchange,
+                                   int force_download);
 
 
 /**