New post-build script pio-tools/timestamp-firmware.py copies firmware
artifacts to timestamped filenames when append_timestamp = 1 is set in
the [tasmota] section of platformio_override.ini. Default off; standard
builds unaffected.
The timestamp is extracted from the ELF symbol table via nm: named PROGMEM
symbols mdate_P and mtime_P in GetBuildDateAndTime() carry __DATE__ and
__TIME__ respectively. Reading them from the ELF guarantees the filename
timestamp matches exactly the one the firmware reports at boot. No -g flag required.
Artifacts written with timestamp suffix (e.g. tasmota-4M-2026-05-01T19-02-06):
.bin, .bin.gz, .factory.bin (ESP32) -> build_output/firmware/
.elf -> build_output/firmware/
.map.gz -> build_output/map/
support_rtc.ino: mtime_P introduced as a named PROGMEM variable so nm can
locate __TIME__ by symbol name on all platforms, including ESP32 where
PSTR() is a no-op. Flash impact: +4 B; all other memory unchanged.
* ESP8266: fix ESP_getMaxAllocHeap() and ESP_getHeapFragmentation()
Both functions returned wrong values: ESP_getMaxAllocHeap() returned
ESP.getFreeHeap() (total free, not largest contiguous block);
ESP_getHeapFragmentation() read ummHeapInfo.maxFreeContiguousBlocks,
which is only valid immediately after a umm_info() heap walk.
Fix: cache the result of umm_max_block_size() in ESP_UpdateHeapMetrics().
The cache is refreshed once per second when SetOption130 is active, and
on demand in CmndStatus() before Status 4 is output. Both getter functions
read the cached value; the call site overhead is a single integer read.
umm_max_block_size() is unconditionally available (UMM_INFO is hardcoded
in the Arduino ESP8266 umm_malloc_cfg.h), so no build flags are required.
Status 4 (StatusMEM) gains two ESP8266-specific fields: MaxFreeBlock (KB)
and Frag (%).
* ESP8266: add heap OOM diagnostics, Status 4 fields, Status 44 dump
OOM event monitoring (requires UMM_INLINE_METRICS or UMM_STATS_FULL):
- ESP_HeapOomCheck(): called once per second; logs the OOM counter delta
when the counter changes ("OOM: count N (+M)")
- ESP_HeapOomTest(): logs current OOM count on demand
Status 4 (StatusMEM) gains additional ESP8266-specific fields when the
corresponding build flags are active:
- OomCount: cumulative out-of-memory events (UMM_INLINE_METRICS or
UMM_STATS_FULL)
- HeapLwm (KB): heap low-watermark since boot (UMM_STATS_FULL)
- MaxAllocSz (bytes): peak single allocation size (UMM_STATS_FULL)
Status 44 (ESP8266-only diagnostic command):
- Triggers umm_info(nullptr, true) to print a full heap block map to
the serial console
- Calls ESP_HeapOomTest() to log the current OOM count
- Returns {"Status44":{"HeapDump":"serial"}}
- Status 44 is accepted regardless of MAX_STATUS
Build flags UMM_STATS_FULL and UMM_INLINE_METRICS can be enabled via
platformio_override.ini build_flags; documented in
platformio_override_sample.ini.
* Add support for multi-byte characters like emojis (💡) in WebButton labels for light device toggle buttons
- Remove the 3-character buffer truncation of light device toggle button labels allowing multi-byte characters like emojis
- Rely on CSS to handle truncation and add `max-width:0` to the td so it respects the provided percentage width instead of expanding to fit content
- Wrap button content in a span with overflow handling to prevent layout breakage
* Use localized `D_BUTTON_TOGGLE` for light device button default text
* Improve UTF-8 support in light device WebButton text
- Add `Utf8Truncate` function in `support.ino` to truncate UTF-8 strings to a max chars limit or max visual width limit
- Truncate light device button text to max 4 chars or max width of 4 before passing to button HTML template
- cache calls to GetWebButton so only called once and update bool var from `set_button` to `has_web_button`.
* Small tweaks to improve clarity in Utf8Truncate on codepoint limits and visual width handling
* Correctness fixes
---------
Co-authored-by: s-hadinger <49731213+s-hadinger@users.noreply.github.com>
The ESP8266 SDK automatically invokes sntp_init() via
netif_sta_status_callback on every WiFi reconnect. This results in repeated
allocations of UDP PCBs (udp_new()), leading to heap exhaustion and
potential lwIP timeout list corruption due to unmatched sntp_stop() calls.
Tasmota does not use the lwIP SNTP client and relies solely on WifiGetNtp()
for time synchronization. To avoid unnecessary resource usage, wrap and
neutralize sntp_init() and sntp_stop() with no-op implementations.
This prevents UDP PCB allocations and avoids issues caused by repeated
initialization during reconnect cycles.
Additionally, a PlatformIO post-build script has been added to validate
that the linker wraps are correctly applied. The script runs after ELF
generation and uses xtensa-lx106-elf-nm to inspect symbols, ensuring that
the __wrap_sntp_init and __wrap_sntp_stop functions are present in the
final firmware. If the wrappers are missing, the build fails.
Confirmed via firmware disassembly:
- Single call site in netif_sta_status_callback
- Requires linker wraps: --wrap=sntp_init,--wrap=sntp_stop
Fixes: #24566
* Fix ESP32 reset during WiFi reconnect when mDNS is active
Explicitly call MDNS.end() before WiFi.disconnect() in support_wifi.ino.
This prevents a race condition or crash where the mDNS service attempts
to query or use the network interface while it is being torn down.
* Fix: removed lines added again.
* Save some ram in esp8266
This will exclude the mutex variable not used by esp8266, saving some ram bytes.
Also removed a double initializzation variable is initialized ad the beginning of the function but it's also reinitialized inside if and else branches
* as suggested
Theo Arends
joluxerandGitHub
s-hadingerandGitHub
SteWersandGitHub
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Jason2866andGitHub
utesselandGitHub
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