gpg: Do not require a trustdb for decryption.

* g10/trustdb.c (init_trustdb): Add and implement arg NO_CREATE.
Change to return an error code.  Change all callers to to pass False
for NO_CREATE.
(tdb_get_ownertrust): New arg NO_CREATE.  Call init_trustdb to test
for a non-existing trustdb.  Change all callers to to pass False for
NO_CREATE.
(tdb_get_min_ownertrust): Ditto.
* g10/trust.c (get_ownertrust_with_min): Add arg NO_CREATE.  Call
init_trustdb for a quick check.
(get_ownertrust_info): Add arg NO_CREATE.
(get_ownertrust_string): Ditto.
* g10/gpgv.c (get_ownertrust_info): Adjust stub.
* g10/test-stubs.c (get_ownertrust_info): Ditto.
* g10/mainproc.c (list_node): Call get_ownertrust_info with NO_CREATE
set.
* g10/pubkey-enc.c (get_it): Ditto.
--

Fixes-commit: effa80e0b5fd8cf9e31a984afe391c2406edee8b

For details see mails on Feb 27 and 28 by dkg, gniibe, and Justus to
gnupg-devel 'test failure on git master with
decrypt-session-key.scm (and: continuous integration?)'

Signed-off-by: Werner Koch <wk@gnupg.org>

1 files changed, 21 insertions, 11 deletions

diff --git a/g10/trust.c b/g10/trust.c
index b1fa3d652..d0ea77efd 100644
--- a/g10/trust.c
+++ b/g10/trust.c
@@ -179,17 +179,18 @@ get_ownertrust (PKT_public_key *pk)
   (void)pk;
   return TRUST_UNKNOWN;
 #else
-  return tdb_get_ownertrust (pk);
+  return tdb_get_ownertrust (pk, 0);
 #endif
 }
 
 
 /*
  * Same as get_ownertrust but this takes the minimum ownertrust value
- * into account, and will bump up the value as needed.
+ * into account, and will bump up the value as needed.  NO_CREATE
+ * inhibits creation of a trustdb it that does not yet exists.
  */
 static int
-get_ownertrust_with_min (PKT_public_key *pk)
+get_ownertrust_with_min (PKT_public_key *pk, int no_create)
 {
 #ifdef NO_TRUST_MODELS
   (void)pk;
@@ -197,8 +198,15 @@ get_ownertrust_with_min (PKT_public_key *pk)
 #else
   unsigned int otrust, otrust_min;
 
-  otrust = (tdb_get_ownertrust (pk) & TRUST_MASK);
-  otrust_min = tdb_get_min_ownertrust (pk);
+  /* Shortcut instead of doing the same twice in the two tdb_get
+   * functions: If the caller asked not to create a trustdb we call
+   * init_trustdb directly and allow it to fail with an error code for
+   * a non-existing trustdb.  */
+  if (no_create && init_trustdb (1))
+    return TRUST_UNKNOWN;
+
+  otrust = (tdb_get_ownertrust (pk, no_create) & TRUST_MASK);
+  otrust_min = tdb_get_min_ownertrust (pk, no_create);
   if (otrust < otrust_min)
     {
       /* If the trust that the user has set is less than the trust
@@ -217,23 +225,25 @@ get_ownertrust_with_min (PKT_public_key *pk)
 
 /*
  * Same as get_ownertrust but return a trust letter instead of an
- * value.  This takes the minimum ownertrust value into account.
+ * value.  This takes the minimum ownertrust value into account.  If
+ * NO_CREATE is set, no efforts for creating a trustdb will be taken.
  */
 int
-get_ownertrust_info (PKT_public_key *pk)
+get_ownertrust_info (PKT_public_key *pk, int no_create)
 {
-  return trust_letter (get_ownertrust_with_min (pk));
+  return trust_letter (get_ownertrust_with_min (pk, no_create));
 }
 
 
 /*
  * Same as get_ownertrust but return a trust string instead of an
- * value.  This takes the minimum ownertrust value into account.
+ * value.  This takes the minimum ownertrust value into account.  If
+ * NO_CREATE is set, no efforts for creating a trustdb will be taken.
  */
 const char *
-get_ownertrust_string (PKT_public_key *pk)
+get_ownertrust_string (PKT_public_key *pk, int no_create)
 {
-  return trust_value_to_string (get_ownertrust_with_min (pk));
+  return trust_value_to_string (get_ownertrust_with_min (pk, no_create));
 }