Guard against launching a second FreeRTOS update task while one is
already running. Without this, calling update() twice (e.g. from both
the polling interval and the initial check interval) could spawn two
concurrent tasks both writing to the same UpdateInfo.
With the single-defer structure from the race fix PR, clearing the
handle only needs to happen in one place — at the top of the deferred
lambda, before any other work.
Address review feedback:
- Move error_str out of public UpdateInfo into file-local TaskResult
- Add container.reset() before vTaskDelete (doesn't call destructors)
- Remove redundant has_progress/progress assignments after move
- Add comment on delete after std::move
Address Copilot review feedback:
- Call container->end() when status_code != HTTP_STATUS_OK (pre-existing
bug, but easy to fix while we're here)
- Update error_str comment to say "update check failure" not "fetch failure"
- Move state computation to main loop callback (avoids 2 extra lambda captures)
- Add error_str field to UpdateInfo so error info rides with the pointer
- Allocate UpdateInfo once at top of fetch_manifest_ (single ownership path)
- Lambda captures only 2 pointers (8 bytes), fits std::function SBO
Reduces ESP8266 flash delta from +480 to ~+288 bytes.
The update task runs in a FreeRTOS thread on ESP32 and was writing
directly to update_info_ std::string fields while the main loop
reads them via API (as StringRef pointers into the string buffer),
MQTT, web server, and Prometheus. This is undefined behavior that
can cause use-after-free crashes when a string reallocation
invalidates a StringRef held by the API serialization path.
Move all update_info_ and state_ writes into the existing defer()
callback so they execute on the main loop. The task now accumulates
results in a local UpdateInfo struct and moves it into update_info_
in the deferred callback, eliminating the cross-thread data race
with zero steady-state memory overhead.
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
Co-authored-by: pre-commit-ci-lite[bot] <117423508+pre-commit-ci-lite[bot]@users.noreply.github.com>
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
Co-authored-by: pre-commit-ci-lite[bot] <117423508+pre-commit-ci-lite[bot]@users.noreply.github.com>
J. Nick Koston