commit 22cd9ea1ecb2fb214cdd77c9b095ac7154e023f4
author Michal Vasko <mvasko@cesnet.cz> Tue Dec 07 10:21:24 2021 +0100
committer Michal Vasko <mvasko@cesnet.cz> Tue Mar 15 11:36:42 2022 +0100
tree 74fc52796c8d628e6de6683649a409869d7cea32
parent b5e206791e9ecfa8b840382f93e6806501080780

date and time BUGFIX handle DST when moving timestamp to UTC

Fixes #1734

src/plugins_types/date_and_time.c

diff --git a/src/plugins_types/date_and_time.c b/src/plugins_types/date_and_time.c
index f849c46..62e304c 100644
--- a/src/plugins_types/date_and_time.c
+++ b/src/plugins_types/date_and_time.c
@@ -17,6 +17,7 @@
 #include "plugins_types.h"
 
 #include <ctype.h>
+#include <errno.h>
 #include <stdint.h>
 #include <stdlib.h>
 #include <string.h>
@@ -52,6 +53,7 @@
     LY_ERR ret = LY_SUCCESS;
     struct lysc_type_str *type_dat = (struct lysc_type_str *)type;
     struct lyd_value_date_and_time *val;
+    struct tm tm;
     uint32_t i;
     char c;
 
@@ -118,6 +120,21 @@
         tzset();
         val->time += timezone;
         val->unknown_tz = 1;
+
+        if (daylight) {
+            /* DST may apply, adjust accordingly */
+            if (!localtime_r(&val->time, &tm)) {
+                ret = ly_err_new(err, LY_ESYS, LYVE_DATA, NULL, NULL, "localtime_r() call failed (%s).", strerror(errno));
+                goto cleanup;
+            } else if (tm.tm_isdst < 0) {
+                ret = ly_err_new(err, LY_EINT, LYVE_DATA, NULL, NULL, "Failed to get DST information.");
+                goto cleanup;
+            }
+            if (tm.tm_isdst) {
+                /* move an hour back */
+                val->time -= 3600;
+            }
+        }
     }
 
     if (format == LY_VALUE_CANON) {