[gimp] app, configure: new --disable-check-update option at configuration.

[Jehan <jehanp src gnome org>]

commit 315665592ceeac4214aa6bf578cdb13cd3ac6642
Author: Jehan <jehan girinstud io>
Date:   Thu Feb 6 21:15:43 2020 +0100

    app, configure: new --disable-check-update option at configuration.
    
    Allows to disable the automatic update check at startup. I believe some
    packagers will want such options, in particular on Linux distribution
    (where they control their own release schedule and won't want GIMP to
    pop new version warning up because they have been slow to update their
    package).
    Note that it is still possible to query version checks manually in the
    about dialog, but the automatic check/popup is gone with this option.

 app/gimp-update.c |  3 +++
 configure.ac      | 11 +++++++++++
 2 files changed, 14 insertions(+)
---
diff --git a/app/gimp-update.c b/app/gimp-update.c
index bfe84dbd79..253f3b9f55 100644
--- a/app/gimp-update.c
+++ b/app/gimp-update.c
@@ -226,7 +226,10 @@ gimp_update_auto_check (GimpCoreConfig *config)
   gint64 prev_update_timestamp;
   gint64 current_timestamp;
 
+  /* Builds with update check deactivated just always return FALSE. */
+#ifdef CHECK_UPDATE
   if (! config->check_updates)
+#endif
     return FALSE;
 
   g_object_get (config,
diff --git a/configure.ac b/configure.ac
index 7e4a25324d..f51fde2e9b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2652,6 +2652,16 @@ AC_ARG_WITH(revision,
 AC_DEFINE_UNQUOTED(GIMP_BUILD_REVISION, "$with_revision",
                    [The revision increment for a same build/version/platform])
 
+AC_ARG_ENABLE(check-update,
+              [  --disable-check-update
+                          GIMP will not look up new version availability on startup],
+              check_update=no,
+              check_update=yes)
+if test "x$check_update" = xyes; then
+  AC_DEFINE(CHECK_UPDATE, 1,
+              [Define to 1 if automatic update check is enabled])
+fi
+
 AC_DEFINE_UNQUOTED(GIMP_BUILD_PLATFORM, "$host_os",
                    [The OS this was built for])
 if test "x$platform_linux" = xyes; then
@@ -3159,6 +3169,7 @@ Extra Binaries:
   gimp-console:              $enable_gimp_console
 
 Optional Features:
+  Check updates at startup:  $check_update
   Levin matting engine:      $have_matting_levin
   Language selection:        $have_iso_codes
   Vector icons:              $enable_vector_icons