From 777019faf0b8f10a897c3ee477d35f9b29f02224 Mon Sep 17 00:00:00 2001
From: NIIBE Yutaka <gniibe@fsij.org>
Date: Fri, 20 Nov 2020 15:35:27 +0900
Subject: [PATCH] gpg: Change API of agent_scd_serialno.

* g10/call-agent.c (agent_scd_serialno): Extend API to allow with
R_SERIALNO == NULL.
* g10/card-util.c (card_status): Use NULL for agent_scd_serialno.
(factory_reset): Likewise.
* g10/skclist.c (build_sk_list): Likewise.

Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>
---
 g10/call-agent.c | 10 ++++++++--
 g10/card-util.c  | 15 +++------------
 g10/skclist.c    |  9 ++-------
 3 files changed, 13 insertions(+), 21 deletions(-)

diff --git a/g10/call-agent.c b/g10/call-agent.c
index cc0da316b..9a3b43d9e 100644
--- a/g10/call-agent.c
+++ b/g10/call-agent.c
@@ -1408,7 +1408,9 @@ agent_scd_serialno (char **r_serialno, const char *demand)
   char *serialno = NULL;
   char line[ASSUAN_LINELENGTH];
 
-  *r_serialno = NULL;
+  if (r_serialno)
+    *r_serialno = NULL;
+
   err = start_agent (NULL, (1 | FLAG_FOR_CARD_SUPPRESS_ERRORS));
   if (err)
     return err;
@@ -1427,7 +1429,11 @@ agent_scd_serialno (char **r_serialno, const char *demand)
       return err;
     }
 
-  *r_serialno = serialno;
+  if (r_serialno)
+    *r_serialno = serialno;
+  else
+    xfree (serialno);
+
   return 0;
 }
 
diff --git a/g10/card-util.c b/g10/card-util.c
index 4da4a53c8..36f096f06 100644
--- a/g10/card-util.c
+++ b/g10/card-util.c
@@ -689,7 +689,6 @@ card_status (ctrl_t ctrl, estream_t fp, const char *serialno)
   int err;
   strlist_t card_list, sl;
   char *serialno0 = NULL;
-  char *serialno1 = NULL;
   int all_cards = 0;
   int any_card = 0;
 
@@ -723,7 +722,7 @@ card_status (ctrl_t ctrl, estream_t fp, const char *serialno)
         tty_fprintf (fp, "\n");
       any_card = 1;
 
-      err = agent_scd_serialno (&serialno1, sl->d);
+      err = agent_scd_serialno (NULL, sl->d);
       if (err)
         {
           if (opt.verbose)
@@ -733,19 +732,16 @@ card_status (ctrl_t ctrl, estream_t fp, const char *serialno)
         }
 
       current_card_status (ctrl, fp, NULL, 0);
-      xfree (serialno1);
-      serialno1 = NULL;
 
       if (!all_cards)
         goto leave;
     }
 
   /* Select the original card again.  */
-  err = agent_scd_serialno (&serialno1, serialno0);
+  err = agent_scd_serialno (NULL, serialno0);
 
  leave:
   xfree (serialno0);
-  xfree (serialno1);
   free_strlist (card_list);
 }
 
@@ -2010,12 +2006,7 @@ factory_reset (void)
 
   /* Then, connect the card again.  */
   if (!err)
-    {
-      char *serialno0;
-
-      err = agent_scd_serialno (&serialno0, NULL);
-      xfree (serialno0);
-    }
+    err = agent_scd_serialno (NULL, NULL);
 
  leave:
   if (locked)
diff --git a/g10/skclist.c b/g10/skclist.c
index a4dffe3d7..c9f7d126a 100644
--- a/g10/skclist.c
+++ b/g10/skclist.c
@@ -131,17 +131,15 @@ build_sk_list (ctrl_t ctrl,
     {
       struct agent_card_info_s info;
       PKT_public_key *pk;
-      char *serialno;
 
       memset (&info, 0, sizeof(info));
       pk = xmalloc_clear (sizeof *pk);
       pk->req_usage = use;
 
       /* Check if a card is available.  If any, use the key as a hint.  */
-      err = agent_scd_serialno (&serialno, NULL);
+      err = agent_scd_serialno (NULL, NULL);
       if (!err)
         {
-          xfree (serialno);
           err = agent_scd_getattr ("KEY-FPR", &info);
           if (err)
             log_error ("error retrieving key fingerprint from card: %s\n",
@@ -382,8 +380,6 @@ enum_secret_keys (ctrl_t ctrl, void **context, PKT_public_key *sk)
           /* Loop over the list of secret keys.  */
           do
             {
-              char *serialno;
-
               name = NULL;
               keyblock = NULL;
               switch (c->state)
@@ -410,10 +406,9 @@ enum_secret_keys (ctrl_t ctrl, void **context, PKT_public_key *sk)
 
                 case 3: /* Init list of card keys to try.  */
                   c->card_keyinfo_list = NULL;
-                  err = agent_scd_serialno (&serialno, NULL);
+                  err = agent_scd_serialno (NULL, NULL);
                   if (!err)
                     {
-                      xfree (serialno);
                       err = agent_scd_keyinfo (NULL, GCRY_PK_USAGE_ENCR,
                                                &c->card_keyinfo_list);
                     }