no setz

esphome/components/time/posix_tz.cpp

@@ -3,6 +3,13 @@
 
 namespace esphome::time {
 
+// Global timezone for ESPTime::from_epoch_local() to use
+static ParsedTimezone global_tz_{};
+
+void set_global_tz(const ParsedTimezone &tz) { global_tz_ = tz; }
+
+const ParsedTimezone &get_global_tz() { return global_tz_; }
+
 namespace internal {
 
 // Helper to parse an unsigned integer from string, updating pointer

esphome/components/time/posix_tz.h

@@ -53,6 +53,14 @@ bool parse_posix_tz(const char *tz_string, ParsedTimezone &result);
 /// @return true on success
 bool epoch_to_local_tm(time_t utc_epoch, const ParsedTimezone &tz, struct tm *out_tm);
 
+/// Set the global timezone used by epoch_to_local_tm() when called without a timezone.
+/// This is called by RealTimeClock::apply_timezone_() to enable ESPTime::from_epoch_local()
+/// to work without libc's localtime().
+void set_global_tz(const ParsedTimezone &tz);
+
+/// Get the global timezone.
+const ParsedTimezone &get_global_tz();
+
 // Internal helper functions exposed for testing
 
 namespace internal {

esphome/components/time/real_time_clock.cpp

@@ -25,17 +25,16 @@ RealTimeClock::RealTimeClock() = default;
 
 void RealTimeClock::dump_config() {
 #ifdef USE_TIME_TIMEZONE
-  int std_hours = -this->parsed_tz_.std_offset_seconds / 3600;
-  int std_mins = abs(this->parsed_tz_.std_offset_seconds % 3600) / 60;
+  const auto &tz = get_global_tz();
+  int std_hours = -tz.std_offset_seconds / 3600;
+  int std_mins = abs(tz.std_offset_seconds % 3600) / 60;
   ESP_LOGCONFIG(TAG, "Timezone: UTC%+d:%02d", std_hours, std_mins);
-  if (this->parsed_tz_.has_dst) {
-    int dst_hours = -this->parsed_tz_.dst_offset_seconds / 3600;
+  if (tz.has_dst) {
+    int dst_hours = -tz.dst_offset_seconds / 3600;
     // Always use M format - tzdata and aioesphomeapi only generate M format rules
-    ESP_LOGCONFIG(TAG, "  DST: UTC%+d, M%d.%d.%d/%" PRId32 " - M%d.%d.%d/%" PRId32, dst_hours,
-                  this->parsed_tz_.dst_start.month, this->parsed_tz_.dst_start.week,
-                  this->parsed_tz_.dst_start.day_of_week, this->parsed_tz_.dst_start.time_seconds / 3600,
-                  this->parsed_tz_.dst_end.month, this->parsed_tz_.dst_end.week, this->parsed_tz_.dst_end.day_of_week,
-                  this->parsed_tz_.dst_end.time_seconds / 3600);
+    ESP_LOGCONFIG(TAG, "  DST: UTC%+d, M%d.%d.%d/%" PRId32 " - M%d.%d.%d/%" PRId32, dst_hours, tz.dst_start.month,
+                  tz.dst_start.week, tz.dst_start.day_of_week, tz.dst_start.time_seconds / 3600, tz.dst_end.month,
+                  tz.dst_end.week, tz.dst_end.day_of_week, tz.dst_end.time_seconds / 3600);
   }
 #endif
   auto time = this->now();
@@ -96,24 +95,23 @@ void RealTimeClock::synchronize_epoch_(uint32_t epoch) {
 
 #ifdef USE_TIME_TIMEZONE
 void RealTimeClock::apply_timezone_(const char *tz) {
+  ParsedTimezone parsed{};
+
   // Handle null input
   if (tz == nullptr) {
     ESP_LOGW(TAG, "Failed to parse timezone: (null)");
-    this->parsed_tz_ = ParsedTimezone{};
+    set_global_tz(parsed);
     return;
   }
 
-  // Set TZ env var for components using libc's localtime() directly
-  // (e.g., sun, datetime, wireguard, deep_sleep)
-  setenv("TZ", tz, 1);
-  tzset();
-
-  // Parse the POSIX TZ string using our custom parser for RealTimeClock::now()
-  if (!parse_posix_tz(tz, this->parsed_tz_)) {
+  // Parse the POSIX TZ string using our custom parser
+  if (!parse_posix_tz(tz, parsed)) {
     ESP_LOGW(TAG, "Failed to parse timezone: %s", tz);
-    // Reset to UTC on parse failure
-    this->parsed_tz_ = ParsedTimezone{};
+    // parsed stays as default (UTC) on failure
   }
+
+  // Set global timezone for all time conversions
+  set_global_tz(parsed);
 }
 #endif
 

esphome/components/time/real_time_clock.h

@@ -47,7 +47,7 @@ class RealTimeClock : public PollingComponent {
 #ifdef USE_TIME_TIMEZONE
     time_t epoch = this->timestamp_now();
     struct tm local_tm;
-    if (epoch_to_local_tm(epoch, this->parsed_tz_, &local_tm)) {
+    if (epoch_to_local_tm(epoch, get_global_tz(), &local_tm)) {
       return ESPTime::from_c_tm(&local_tm, epoch);
     }
     // Fallback to UTC if parsing failed
@@ -74,7 +74,6 @@ class RealTimeClock : public PollingComponent {
   void synchronize_epoch_(uint32_t epoch);
 
 #ifdef USE_TIME_TIMEZONE
-  ParsedTimezone parsed_tz_{};
   void apply_timezone_(const char *tz);
 #endif
 

esphome/core/time.h

@@ -7,6 +7,10 @@
 #include <span>
 #include <string>
 
+#ifdef USE_TIME_TIMEZONE
+#include "esphome/components/time/posix_tz.h"
+#endif
+
 namespace esphome {
 
 template<typename T> bool increment_time_value(T &current, uint16_t begin, uint16_t end);
@@ -105,11 +109,20 @@ struct ESPTime {
    * @return The generated ESPTime
    */
   static ESPTime from_epoch_local(time_t epoch) {
+#ifdef USE_TIME_TIMEZONE
+    struct tm local_tm;
+    if (time::epoch_to_local_tm(epoch, time::get_global_tz(), &local_tm)) {
+      return ESPTime::from_c_tm(&local_tm, epoch);
+    }
+    // Fallback to UTC if conversion failed
+    return ESPTime::from_epoch_utc(epoch);
+#else
     struct tm *c_tm = ::localtime(&epoch);
     if (c_tm == nullptr) {
       return ESPTime{};  // Return an invalid ESPTime
     }
     return ESPTime::from_c_tm(c_tm, epoch);
+#endif
   }
   /** Convert an UTC epoch timestamp to a UTC time ESPTime instance.
    *