Documents why the largest allocatable block on a non-PSRAM observer walks down in
16 KiB steps at every TLS reconnect, and what to do about it.
The framework builds mbedTLS with the symmetric buffer configuration
(CONFIG_MBEDTLS_SSL_MAX_CONTENT_LEN 16384), so each broker slot holds two 16 KiB
record buffers in internal DRAM and two slots cost 64 KiB on a board with about
80 KiB free. Confirmed against the sdkconfig the Heltec env actually links, not
the IDF 5.3 libs package that belongs to the esp32c6 env.
Rebuilding only the mbedTLS archives with an asymmetric outbound buffer of 4 KiB
is ABI-safe, because in_buf/out_buf are heap pointers sized in ssl_setup() and no
public struct embeds a CONTENT_LEN-sized array. Dropping KEEP_PEER_CERTIFICATE is
not, since it changes mbedtls_ssl_session layout, so it is excluded.
Also records two traps worth not rediscovering: esp32-arduino-lib-builder's
release/v4.4 clones its dependencies at master and no longer resolves, and
pointing platform_packages at a file:// framework copy overwrites the shared
package for every other project on the machine.
Picks up upstream MeshCore 1.17.0 and the dev commits that followed it.
Notable upstream content:
- 1.17.0 version/build-date bump in the example MyMesh headers.
- anon_req hardening: reply_path_len is now uint8_t with an isValidPathLen()
bounds check and a 0xFF sentinel; reply_path_hash_size is gone.
- LR2021 support (Meshnology W12, Seeed MeshTracker X1) incl. side detectors,
multi-SF and the new `extra.sf` get/set CLI.
- CustomLFS 0.2.2 -> 0.2.3 (GD25Q64C support).
- kiss_modem envs for several nRF52 variants; ThinkNode M6 GPS/flash fixes.
Conflicts resolved:
- platformio.ini: took upstream's CustomLFS 0.2.3, kept our lib_ignore for
the vendored PsychicMqttClient.
- CommonCLI.h: kept both upstream's USE_LR2021 configSideDetectors() hook and
our fault-alert callbacks.
NodePrefs gains upstream's extra_sf[4], which is not registered with
ConfigSerializer, so /prefs.json layout is unchanged.
Verified: 275/275 native host tests pass; Heltec_v3_repeater_observer_mqtt,
Heltec_v3_repeater and heltec_v4_repeater_observer_mqtt all build.
PA PL1 re-targets the PA's DC-DC supply rail rather than selecting a
logic-level gain, and the serial CLI is serviced on every main-loop pass
regardless of whether a transmit is in flight. A `set radio.fem.txgain`
write could therefore move the rail mid-transmit, while the SX1262 was
still driving the PA at full input power.
Record the requested level in setPAGainEnable() and drive the pin from
setTxModeEnable(), which runs from onBeforeTransmit() ahead of
startTransmit(). The level only matters while transmitting, so deferring
costs nothing.
Document that the pref is saved immediately but applied at the next
transmit, so `get radio.fem.txgain` can lead the hardware until then.
Improve companion BLE delivery and idempotent remote CLI retries, make FPF7 persistence atomic with FPF6 migration, verify staged OTA data on resume, and clarify filter policy wildcard and BlackHole semantics.
Neighbors publication was gated on BOARD_HAS_PSRAM. Removing that gate alone
was not enough: the feature built but was inert without PSRAM, because three
allocation sites asked for MALLOC_CAP_SPIRAM (which returns null with no
PSRAM), the bridge's persistent buffer was allocated inside a BOARD_HAS_PSRAM
block, and neighborDiscoverReady() rejected every pass at runtime on
psramFound(). The entry table also did not fit: finishNeighborDiscover put
pubkey_hex[50][65] plus entries[50] on the stack, a 4752-byte frame against
the mesh loop task's 8 KB.
- Gate on MAX_NEIGHBOURS plus PSRAM or an explicit per-variant
MQTT_NEIGHBORS_WITHOUT_PSRAM opt-in.
- Move the entry table and its hex strings into one heap block sized to the
pass; the frame drops from 4752 to 304 bytes.
- Prefer PSRAM and fall back to internal DRAM in the mesh-side allocations
and the ArduinoJson pool; hoist the bridge's persistent buffer out of the
BOARD_HAS_PSRAM block (psram_malloc already falls back).
- Keep the runtime psramFound() check only where the buffers are sized for
PSRAM, so a board whose PSRAM failed to init still refuses.
- Size for internal DRAM without PSRAM: 4 KB text buffer and 20 entries per
publish, keeping the pool to a single block and the peak near 13 KB rather
than ~35 KB. Oversized tables truncate and report total_neighbors as before.
Enabled on the ESP32-S3 observer envs (Heltec V3/WSL3, RAK3112, Heltec
Tracker v1.1/v2). Left off for the classic ESP32 T-LoRa V2.1-1.6, which is
already limited to one active TLS slot.
Costs ~7.4 KB static DRAM on repeaters and ~9.6 KB on room servers. The
prefs layout is unchanged, so this is neutral for existing devices.
Absorbs 106 upstream commits. Seven files conflicted; the substantive one
was upstream's new JSON ConfigSerializer (PR #2982), which replaces the
binary /com_prefs layout with /prefs.json and makes NodePrefs a
ConfigSerializer subclass.
Prefs migration
- Adopt upstream's ConfigSerializer. writeCommonPrefsImage() and its
documented offsets (0-294) are deleted, along with the now-unreachable
saveCommonPrefsImageAtomically()/CommonPrefsFileStore atomic rename path.
- Load order is /prefs.json, then /com_prefs, then /node_prefs. Upstream
dropped the /node_prefs fallback; it is restored here so devices that
never advanced past that filename keep their config.
- Legacy files are never removed, so migration cannot destroy its own
source and a deferred or failed save simply retries next boot.
- /com_prefs is treated as a format migration only, not an "upgrade", so
it does not trip the bridge.source tx->rx flip on existing nodes.
- The MQTTPrefsAtomicStore legacy gate is retained: the observer tail
recovered from an old-format file still commits to /mqtt_prefs before
/prefs.json is written.
- MQTTPrefs and /mqtt_prefs are untouched; savePrefs keeps its save_mqtt
parameter and now returns upstream's bool.
Fixes to upstream code
- RadioPrefs::structure() bound both "rxgain" and "fem_rxgain" to
rx_boosted_gain, so radio_fem_rxgain was never persisted. Bound to the
correct field.
- discovery_mod_timestamp was dropped from structure(); it gates
'since'-filtered DISCOVER replies and is set on every config change, so
losing it would silently stop discovery responses after a reboot. Added
as "disc_mod".
Merge artifacts repaired
- Restored bblanchon/ArduinoJson to the native test env; a clean but wrong
auto-merge at the lib_deps block boundary dropped it and broke all 19
host test suites.
- Migrated the fork's WebConfig UITask screens off the removed
DisplayDriver::Color enum to upstream's UIColor element types.
- Removed duplicate getCADEnabled() definitions in companion MyMesh.cpp
and simple_sensor SensorMesh.cpp that both sides had added.
- Dropped memset(&_prefs, 0, ...) in the four example meshes; NodePrefs now
has a vtable. guard gains an initializer that memset used to provide.
Other resolutions
- simple_room_server keeps both the fork's discover.* commands and
upstream's new room.post.
- docs/payloads.md taken from upstream, undoing content earlier merges had
reverted (Control data section, split login tables).
Verified: 273/273 host tests pass across native and native_kiss_modem;
Heltec v3 repeater, repeater_observer_mqtt, room_server_observer_mqtt,
sensor, and companion_radio_ble all build clean.
ripplebiz
mikecarper
Kevin Le
agessaman
Jarosław Domański