Allow setting export filters when exporting keys

* src/context.h (struct gpgme_context): New field export_filter.
* src/engine-backend.h (struct engine_ops): Add arg export_filter to
field 'export' and field 'export_ext'.
* src/engine-gpg.c (export_common): Add arg export_filter and pass
option --export-filter with argument value to gpg.
(gpg_export, gpg_export_ext): Add arg export_filter and pass it to
export_common. Adjust all callers of the two functions.
* src/engine-gpgsm.c (gpgsm_export, gpgsm_export_ext): Add dummy arg
export_filter.
* src/gpgme.c (gpgme_release): Free 'export_filter'.
(gpgme_set_ctx_flag, gpgme_get_ctx_flag): New flag "export-filter".

* tests/run-export.c (main): Add option --export-filter.
--

This makes the --export-filter option available in the GPGME API for
key exports.

GnuPG-bug-id: 8033

1 files changed, 6 insertions, 0 deletions

diff --git a/doc/gpgme.texi b/doc/gpgme.texi
index 90100979..d1c1a3f1 100644
--- a/doc/gpgme.texi
+++ b/doc/gpgme.texi
@@ -3270,6 +3270,12 @@ the expiration time to use for key signature expiration.  Valid values
 are documented in the GnuPG manual and the gpg man page under
 the option @option{--default-cert-expire}.
 
+@item "export-filter"
+@since{2.0.2}
+The string given in @var{value} is passed to the GnuPG engine to use as
+filter when exporting keys.  Valid values are documented in the GnuPG
+manual and the gpg man page under the option @option{--export-filter}.
+
 @item "key-origin"
 @since{1.16.1}
 The string given in @var{value} is passed to the GnuPG engine to set