core: Add cert-notation support and extended-edit

* src/context.h (gpgme_context): Add new flag for extended-edit.
* src/engine-gpg.c (append_args_from_sig_notations): Add flags to
control the kind of notations.
(gpg_edit): Respect extended-edit and notations.
(gpg_encrypt_sign, gpg_sign): Update call to
append_args_from_sig_notations.
* src/gpgme.c (gpgme_set_ctx_flag, gpgme_get_ctx_flag): Support
extended-edit.
* NEWS, doc/gpgme.texi: Mention extended-edit.

--
This provides a way to get the extended key-edit interface without
breaking bad state machines that rely on the current command flow.

A use case for this is to enable multiple local signatures, which
can be used together with annotations for:

GnuPG-Bug-Id: T4734

NEWS

@@ -1,6 +1,7 @@
 Noteworthy changes in version 1.14.0 (unreleased)
 -------------------------------------------------
 
+ * New context flag "extended-edit" to enable expert key edit. [#4734]
 
  * Interface changes relative to the 1.13.1 release:
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

doc/gpgme.texi

@@ -3150,6 +3150,10 @@ trust-model changes the default trust-model for future operations.
 A change in the trust-model also can have unintended side effects, like
 rebuilding the trust-db.
 
+@item "extended-edit"
+This flag passes the option @option{--expert} to gpg key edit.  This
+can be used to get additional callbacks in @code{gpgme_op_edit}.
+
 @end table
 
 This function returns @code{0} on success.

src/context.h

@@ -128,6 +128,9 @@ struct gpgme_context
    * after the operation.  */
   unsigned int ignore_mdc_error : 1;
 
+  /* Pass --expert to gpg edit key. */
+  unsigned int extended_edit : 1;
+
   /* Flags for keylist mode.  */
   gpgme_keylist_mode_t keylist_mode;
 

src/engine-gpg.c

@@ -1848,8 +1848,13 @@ append_args_from_sender (engine_gpg_t gpg, gpgme_ctx_t ctx)
 }
 
 
+#define NOTATION_FLAG_SIG  1 /* Use --sig-notation (default)*/
+#define NOTATION_FLAG_CERT 2 /* Use --cert-notation */
+#define NOTATION_FLAG_SET  3 /* Use --set-notation */
+
 static gpgme_error_t
-append_args_from_sig_notations (engine_gpg_t gpg, gpgme_ctx_t ctx /* FIXME */)
+append_args_from_sig_notations (engine_gpg_t gpg, gpgme_ctx_t ctx /* FIXME */,
+                                int flags)
 {
   gpgme_error_t err = 0;
   gpgme_sig_notation_t notation;
@@ -1890,7 +1895,14 @@ append_args_from_sig_notations (engine_gpg_t gpg, gpgme_ctx_t ctx /* FIXME */)
 	    }
 
 	  if (!err)
-	    err = add_arg (gpg, "--sig-notation");
+            {
+              if ((flags & NOTATION_FLAG_SET))
+                err = add_arg (gpg, "--set-notation");
+              else if ((flags & NOTATION_FLAG_CERT))
+                err = add_arg (gpg, "--cert-notation");
+              else
+                err = add_arg (gpg, "--sig-notation");
+            }
 	  if (!err)
 	    err = add_arg (gpg, arg);
 
@@ -1941,10 +1953,15 @@ gpg_edit (void *engine, int type, gpgme_key_t key, gpgme_data_t out,
   gpgme_error_t err;
 
   err = add_arg (gpg, "--with-colons");
+
+  if (!err && ctx->extended_edit)
+    err = add_arg (gpg, "--expert");
   if (!err)
     err = append_args_from_signers (gpg, ctx);
   if (!err)
-  err = add_arg (gpg, type == 0 ? "--edit-key" : "--card-edit");
+    err = append_args_from_sig_notations (gpg, ctx, NOTATION_FLAG_CERT);
+  if (!err)
+    err = add_arg (gpg, type == 0 ? "--edit-key" : "--card-edit");
   if (!err)
     err = add_data (gpg, out, 1, 1);
   if (!err)
@@ -2254,7 +2271,7 @@ gpg_encrypt_sign (void *engine, gpgme_key_t recp[],
     err = append_args_from_sender (gpg, ctx);
 
   if (!err)
-    err = append_args_from_sig_notations (gpg, ctx);
+    err = append_args_from_sig_notations (gpg, ctx, NOTATION_FLAG_SIG);
 
   /* Tell the gpg object about the data.  */
   if (!err)
@@ -3228,7 +3245,7 @@ gpg_sign (void *engine, gpgme_data_t in, gpgme_data_t out,
   if (!err)
     err = append_args_from_sender (gpg, ctx);
   if (!err)
-    err = append_args_from_sig_notations (gpg, ctx);
+    err = append_args_from_sig_notations (gpg, ctx, NOTATION_FLAG_SIG);
 
   if (gpgme_data_get_file_name (in))
     {

src/gpgme.c

@@ -566,6 +566,10 @@ gpgme_set_ctx_flag (gpgme_ctx_t ctx, const char *name, const char *value)
       if (!ctx->trust_model)
         err = gpg_error_from_syserror ();
     }
+  else if (!strcmp (name, "extended-edit"))
+    {
+      ctx->extended_edit = abool;
+    }
   else
     err = gpg_error (GPG_ERR_UNKNOWN_NAME);
 
@@ -623,6 +627,10 @@ gpgme_get_ctx_flag (gpgme_ctx_t ctx, const char *name)
     {
       return ctx->auto_key_locate? ctx->auto_key_locate : "";
     }
+  else if (!strcmp (name, "extended-edit"))
+    {
+      return ctx->extended_edit ? "1":"";
+    }
   else
     return NULL;
 }