ctf: Use g_time_val_from_iso8601 instead of g_date_time_new_from_iso8601

g_date_time_new_from_iso8601 was introduced in glib 2.56, which is quite
recent.  To support build with older glibs, change the code to use
g_time_val_from_iso8601 instead, introduced in glib 2.12.

The code in question only uses this function to validate that the passed
string is ISO8601-compliant, it doesn't use the resulting time value.

The problem of g_time_val_from_iso8601 is that its result is not year
2038-safe on 32-bit systems.  We can expect that by then, that function
will have been removed from glib, forcing us to update our code.

Change-Id: I2f4fdfce9020ecefcfb5d653a3885d343e49bd76
Signed-off-by: Simon Marchi <simon.marchi@efficios.com>
Reviewed-on: https://review.lttng.org/c/babeltrace/+/1245
Reviewed-by: Michael Jeanson <mjeanson@efficios.com>
Reviewed-by: Philippe Proulx <eeppeliteloop@gmail.com>

diff --git a/plugins/ctf/fs-sink/fs-sink-trace.c b/plugins/ctf/fs-sink/fs-sink-trace.c
index 375fff970996cdd5a5da14c5243b5c46a067e8f2..c6989ccc0929fee1c65d95430f4376caff6d8ed9 100644 (file)
--- a/plugins/ctf/fs-sink/fs-sink-trace.c
+++ b/plugins/ctf/fs-sink/fs-sink-trace.c
@@ -139,18 +139,16 @@ GString *make_unique_trace_path(const char *path)
 static
 int lttng_validate_datetime(const char *datetime)
 {
-       GTimeZone *default_tz;
-       GDateTime *gdatetime = NULL;
+       GTimeVal tv;
        int ret = -1;
 
-       default_tz = g_time_zone_new_utc();
-       if (!default_tz) {
-               BT_LOGD("Failed to allocate timezone");
-               goto end;
-       }
-
-       gdatetime = g_date_time_new_from_iso8601(datetime, default_tz);
-       if (!gdatetime) {
+       /*
+        * We are using g_time_val_from_iso8601, as the safer/more modern
+        * alternative, g_date_time_new_from_iso8601, is only available in
+        * glib >= 2.56, and this is sufficient for our use case of validating
+        * the format.
+        */
+       if (!g_time_val_from_iso8601(datetime, &tv)) {
                BT_LOGD("Couldn't parse datetime as iso8601: date=\"%s\"", datetime);
                goto end;
        }
@@ -158,16 +156,6 @@ int lttng_validate_datetime(const char *datetime)
        ret = 0;
 
 end:
-       if (default_tz) {
-               g_time_zone_unref(default_tz);
-               default_tz = NULL;
-       }
-
-       if (gdatetime) {
-               g_date_time_unref(gdatetime);
-               gdatetime = NULL;
-       }
-
        return ret;
 }