* sm/Makefile.am (AM_CFLAGS): Add npth flags.
(common_libs): Use npth version of the lib.
(gpgsm_LDADD): Add npth libs.
* sm/gpgsm.c (oUseKeyboxd, oKeyboxdProgram): New.
(opts): New options --use-keyboxd and --keyboxd-program.
(main): Set them.
(gpgsm_deinit_default_ctrl): New.
(main): Call it.
* sm/server.c (gpgsm_server): Ditto.
* sm/gpgsm.h (opt): Add fields use_keyboxd and keyboxd_program.
(keydb_local_s): New type.
(struct server_control_s): Add field keybd_local.
* sm/keydb.c: Include assuan.h, asshelp.h, and kbx-client-util.h.
(struct keydb_local_s): New.
(struct keydb_handle): Add fields for keyboxd use.
(gpgsm_keydb_deinit_session_data): New.
(warn_version_mismatch): New.
(create_new_context): New.
(open_context): New.
(keydb_new): Implement keyboxd mode.
(keydb_release): Ditto.
(keydb_get_resource_name): Ditto.
* sm/keydb.c: Add stub support for all other functions.