[evolution/gnome-3-28] Bug 794628 - Don't preload timezones on libical 3.0.2+

[Milan Crha <mcrha src gnome org>]

commit 3d81b8a65e8a2589c67688980fe50002023ef25d
Author: Dan Nicholson <nicholson endlessm com>
Date:   Tue Mar 27 17:32:48 2018 +0200

    Bug 794628 - Don't preload timezones on libical 3.0.2+

 src/modules/calendar/e-cal-base-shell-backend.c |   29 +++++++++++++++++++++++
 1 files changed, 29 insertions(+), 0 deletions(-)
---
diff --git a/src/modules/calendar/e-cal-base-shell-backend.c b/src/modules/calendar/e-cal-base-shell-backend.c
index 245ac45..6de48a8 100644
--- a/src/modules/calendar/e-cal-base-shell-backend.c
+++ b/src/modules/calendar/e-cal-base-shell-backend.c
@@ -32,6 +32,26 @@
 
 #include "e-cal-base-shell-backend.h"
 
+/*
+ * FIXME: Remove this when there's a build time dependency on libical
+ * 3.0.4 (where this is fixed). See
+ * https://github.com/libical/libical/pull/335 and the implementation in
+ * https://github.com/libical/libical/blob/master/src/libical/icalversion.h.cmake.
+ */
+#if defined(ICAL_CHECK_VERSION) && defined(ICAL_MAJOR_VERSION) && defined(ICAL_MINOR_VERSION) && 
defined(ICAL_MICRO_VERSION)
+#undef ICAL_CHECK_VERSION
+#define ICAL_CHECK_VERSION(major,minor,micro)                          \
+    (ICAL_MAJOR_VERSION > (major) ||                                   \
+    (ICAL_MAJOR_VERSION == (major) && ICAL_MINOR_VERSION > (minor)) || \
+    (ICAL_MAJOR_VERSION == (major) && ICAL_MINOR_VERSION == (minor) && \
+    ICAL_MICRO_VERSION >= (micro)))
+#else
+#if defined(ICAL_CHECK_VERSION)
+#undef ICAL_CHECK_VERSION
+#endif
+#define ICAL_CHECK_VERSION(major,minor,micro) (0)
+#endif
+
 #define E_CAL_BASE_SHELL_BACKEND_GET_PRIVATE(obj) \
        (G_TYPE_INSTANCE_GET_PRIVATE \
        ((obj), E_TYPE_CAL_BASE_SHELL_BACKEND, ECalBaseShellBackendPrivate))
@@ -232,11 +252,14 @@ e_cal_base_shell_backend_class_init (ECalBaseShellBackendClass *class)
 static void
 e_cal_base_shell_backend_init (ECalBaseShellBackend *cal_base_shell_backend)
 {
+#if !ICAL_CHECK_VERSION(3, 0, 2)
        icalarray *builtin_timezones;
        gint ii;
+#endif
 
        cal_base_shell_backend->priv = E_CAL_BASE_SHELL_BACKEND_GET_PRIVATE (cal_base_shell_backend);
 
+#if !ICAL_CHECK_VERSION(3, 0, 2)
        /* XXX Pre-load all built-in timezones in libical.
         *
         *     Built-in time zones in libical 0.43 are loaded on demand,
@@ -247,6 +270,11 @@ e_cal_base_shell_backend_init (ECalBaseShellBackend *cal_base_shell_backend)
         *     loading all built-in time zones now, so libical's internal
         *     time zone array will be fully populated before any threads
         *     are spawned.
+        *
+        *     This is apparently fixed with additional locking in
+        *     libical 3.0.1 and 3.0.2:
+        *     https://github.com/libical/libical/releases/tag/v3.0.1
+        *     https://github.com/libical/libical/releases/tag/v3.0.2
         */
        builtin_timezones = icaltimezone_get_builtin_timezones ();
        for (ii = 0; ii < builtin_timezones->num_elements; ii++) {
@@ -259,6 +287,7 @@ e_cal_base_shell_backend_init (ECalBaseShellBackend *cal_base_shell_backend)
                 * icaltimezone_load_builtin_timezone(). */
                icaltimezone_get_component (zone);
        }
+#endif
 }
 
 void