gpg,gpgsm: Move use-keyboxd to the new conf file common.conf

* common/comopt.c, common/comopt.h: New.
* common/Makefile.am: Add them.
* g10/gpg.c: Include comopt.h.
(main): Also parse common.conf.
* sm/gpgsm.c: Include comopt.h.
(main): Set a flag for the --no-logfile option.  Parse common.conf.

* tools/gpgconf-comp.c (known_options_gpg): Remove "use-keyboxd", add
pseudo option "use_keyboxd".
(known_pseudo_options_gpg): Add pseudo option "use_keyboxd".
(known_options_gpgsm): Remove "use-keyboxd".

* tests/openpgp/defs.scm (create-gpghome): Create common.conf.

* doc/examples/common.conf: New.
--

Note that --use-keybox still works but prints a warning.  We will
eventually remove this option becuase it was marked as an experimental
feature anyway.

It would be too confusing if gpg and gpgsm use different key storages.
Further, other components (e.g. dirmngr or gpg-wks-client) which call
gpg or gpgsm need to be aware that the keyboxd is used and pass that
option on the command line.  Now that common.conf is always read (even
if --no-options is used) those tools will work instantly.

doc/Makefile.am

@@ -24,6 +24,7 @@ include $(top_srcdir)/am/cmacros.am
 examples = examples/README examples/scd-event examples/trustlist.txt	\
 	   examples/VS-NfD.prf examples/Automatic.prf                   \
            examples/debug.prf  examples/qualified.txt                   \
+	   examples/common.conf                                         \
 	   examples/systemd-user/README 				\
 	   examples/systemd-user/dirmngr.service 			\
 	   examples/systemd-user/dirmngr.socket				\

doc/examples/README

@@ -11,3 +11,5 @@ gpgconf.conf    A sample configuration file for gpgconf.
 systemd-user    Sample files for a Linux-only init system.
 
 qualified.txt   Sample file for qualified.txt.
+
+common.conf     Sample file for common options.

doc/examples/common.conf

@@ -0,0 +1,22 @@
+# common.conf - common defaults for all components.
+#
+# This file may provide defaults as well as options which needs to be
+# synchronized between components.  As usual this file is read from
+# the system wide config directory (e.g. /etc/gnupg/common.conf) as
+# well as from the home directory (e.g. ~/.gnupg.common.conf).
+
+
+# Uncomment to enable the use if the keybox daemon (keyboxd) by gpg
+# and gpgsm.
+#use-keyboxd
+
+# For testing ist is somethimes useful to use a different binary
+# of keybox.  This option can be used to speicify this.
+#keyboxd-program /foo/bar/keyboxd
+
+# For the daemons (gpg-agent, scdaemon, dirmngr, keyboxd) it is often
+# useful to define a shared logging destination.  This is either the
+# standard logging socket (socket://) or a tcp server (tcp://ip:port).
+# If a file name is given the name of the component is internally
+# appended.
+#socket://

doc/gpg.texi

@@ -2476,7 +2476,8 @@ opposite meaning. The options are:
   signatures.  Defaults to yes.
 
   @item bulk-import
-  When used with --use-keyboxd do the import within a single
+  When used the keyboxd (option "use-keyboxd" in @file{common.conf})
+  do the import within a single
   transaction.  This is an experimental feature.
 
   @item import-minimal
@@ -3753,6 +3754,12 @@ current home directory (@pxref{option --homedir}).
   name may be changed on the command line (@pxref{gpg-option --options}).
   You should backup this file.
 
+  @item common.conf
+  @efindex common.conf
+  This is an optional configuration file read by @command{@gpgname} on
+  startup.  It may contain options pertaining to all components of
+  GnuPG.  Its current main use is for the "use-keyboxd" option.
+
 @end table
 
 Note that on larger installations, it is useful to put predefined files

doc/gpgsm.texi

@@ -853,6 +853,11 @@ may not be entered and the option may not be abbreviated.  This default
 name may be changed on the command line (@pxref{gpgsm-option --options}).
 You should backup this file.
 
+@item common.conf
+@efindex common.conf
+This is an optional configuration file read by @command{gpgsm} on
+startup.  It may contain options pertaining to all components of
+GnuPG.  Its current main use is for the "use-keyboxd" option.
 
 @item policies.txt
 @efindex policies.txt