doc,tests: Require use of ctx_flag before use of session_key.

* doc/gpgme.texi: Document requirements of verifying that it is OK to
use session_key.
* tests/run-decrypt.c: Ensure that we fail if we're unable to access
the session key, so that we do not violate the guidance above.

Signed-off-by: Daniel Kahn Gillmor <[email protected]>

Changed the description

 -@code{gpgme_set_ctx_flag (ctx, "export-session-key")} returns
 -@code{GPG_ERR_NO_ERROR} or @code{gpgme_get_ctx_flag (ctx,
 -"export-session-key")} returns @code{"1"}.
 +@code{gpgme_set_ctx_flag (ctx, "export-session-key")} returns success
 +or @code{gpgme_get_ctx_flag (ctx, "export-session-key")} returns true
 +(non-empty string).

to get gpgme_get_ctx_flag for boolean values in sync with its own
description.

Note that I don't agree with the above suggestion but it does not
really harm to have it in the man page.

Signed-off-by: Werner Koch <[email protected]>

2 files changed, 28 insertions, 6 deletions

diff --git a/doc/gpgme.texi b/doc/gpgme.texi
index fd396e02..4f899a9e 100644
--- a/doc/gpgme.texi
+++ b/doc/gpgme.texi
@@ -4814,6 +4814,11 @@ set to export session keys (see @code{gpgme_set_ctx_flag,
 "export-session-key"}), and a session key was available for the most
 recent decryption operation.  Otherwise, this is a null pointer.
 
+You must not try to access this member of the struct unless
+@code{gpgme_set_ctx_flag (ctx, "export-session-key")} returns success
+or @code{gpgme_get_ctx_flag (ctx, "export-session-key")} returns true
+(non-empty string).
+
 @end table
 @end deftp
 
diff --git a/tests/run-decrypt.c b/tests/run-decrypt.c
index 65624d09..07a8747f 100644
--- a/tests/run-decrypt.c
+++ b/tests/run-decrypt.c
@@ -174,9 +174,25 @@ main (int argc, char **argv)
       gpgme_set_ctx_flag (ctx, "full-status", "1");
     }
   if (export_session_key)
-    gpgme_set_ctx_flag (ctx, "export-session-key", "1");
+    {
+      err = gpgme_set_ctx_flag (ctx, "export-session-key", "1");
+      if (err)
+        {
+          fprintf (stderr, PGM ": error requesting exported session key: %s\n",
+                   gpgme_strerror (err));
+          exit (1);
+        }
+    }
   if (override_session_key)
-    gpgme_set_ctx_flag (ctx, "override-session-key", override_session_key);
+    {
+      err = gpgme_set_ctx_flag (ctx, "overrride-session-key", "1");
+      if (err)
+        {
+          fprintf (stderr, PGM ": error overriding session key: %s\n",
+                   gpgme_strerror (err));
+          exit (1);
+        }
+    }
 
   err = gpgme_data_new_from_stream (&in, fp_in);
   if (err)
@@ -201,10 +217,11 @@ main (int argc, char **argv)
       fprintf (stderr, PGM ": decrypt failed: %s\n", gpgme_strerror (err));
       exit (1);
     }
-  if (result) {
-    print_result (result);
-    print_data (out);
-  }
+  if (result)
+    {
+      print_result (result);
+      print_data (out);
+    }
 
   gpgme_data_release (out);
   gpgme_data_release (in);