PR #1908 silent-restarts on exit from any wifi-using activity to defuse
LWIP/mbedTLS heap fragmentation, but two of the wifi-using paths slipped
through that audit:
KOReaderAuthActivity (Settings -> KOReader sync -> Authenticate)
OtaUpdateActivity (Settings -> Check for update, back-out paths)
Both used WiFi.disconnect + WiFi.mode(WIFI_OFF) on exit and returned
control to Settings, leaving ~50KB of contiguous heap stranded for the
rest of the session.
Mirror the FontDownloadActivity pattern: if WiFi was activated,
disconnect and silentRestart. OTA's success path is unchanged:
SHUTTING_DOWN already calls plain ESP.restart() so the new firmware
boots normally; only the cancel/fail/no-update back-out paths now go
through silentRestart().
Did you use AI tools to help write this code? partial
WiFi/LWIP/netif teardown scatters long-lived allocations across the
heap, leaving ~50KB of contiguous space unrecoverable without a reboot.
Reboot the SoC on exit from any wifi-using activity to guarantee a clean
heap. An RTC_NOINIT flag survives the reboot and tells setup() to skip
the boot splash and route the user back where they came from:
- File transfer / Calibre / OPDS / Font download -> home
- KOReader sync -> currently-open EPUB
Activities check WiFi.getMode() before rebooting, so backing out of the
network mode menu without joining doesn't trigger a cycle. KOSync also
esp_wifi_stop()s after the sync result so the radio is off while the
user reads it; full teardown happens at the reboot.
## Additional Context
The silent reboot skips the booting splash screen - it visibly looks
like a screen refresh. This does cause a disconnection/reconnection blip
for developers actively pulling logs over serial, but `pio device
monitor` and the like successfully reconnect and feed in the early boot
serial.
as an example:
```
[256676] [DBG] [ACT] Exiting activity: KOReaderSync
[256706] [DBG] [MAIN] Silent restart (target=reader)
ESP-ROM:esp32c3-api1-20210207
Build:Feb 7 2021
rst:0xc (RTC_SW_CPU_RST),boot:0xf (SPI_FAST_FLASH_BOOT)
Saved PC:0x403872bc
SPIWP:0xee
mode:DIO, clock div:1
load:0x3fcd72a0,len:0x990
load:0x403cbf10,len:0xac8
load:0x403ce710,len:0x4d28
entry 0x403cbf10
[22] [INF] [MAIN] Hardware detect: X4
[29] [SD] SD card detected
[43] [DBG] [CPS] Settings loaded from file
[58] [DBG] [KRS] Loaded KOReader credentials for user: jeremydk
[69] [DBG] [OPS] Loaded 1 OPDS servers from file
[69] [DBG] [UI] Using Lyra theme
[70] [DBG] [MAIN] Starting CrossPoint version 1.2.0-dev-detached-bde75787
...
[203] [DBG] [ACT] Entering activity: Reader
[211] [DBG] [EBP] Loading ePub: /Halting State - Charles Stross.epub
[221] [DBG] [BMC] Loaded cache data: 51 spine, 41 TOC entries
[246] [DBG] [CSS] Loaded 41 rules from cache
[247] [DBG] [EBP] Loaded ePub: /Halting State - Charles Stross.epub
```
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? _PARTIALLY_
## Summary
* **What is the goal of this PR?**
I was seeing hangs during File Transfer. Troubleshooting via serial
showed it had to do with the SHUTTING_DOWN state. Strengthened the WiFi
State Machine a bit and added self-healing. Additionally, I found it
obnoxious to need to keep referring to serial for my wifi strength, so a
dBm meter is added opposing the SSID when on the File Transfer page.
* **What changes are included?**
The dBm meter was at risk of causing rapid screen updates (if, say, we
hovered right around a threshold), so I've implemented a basic
hysteresis around this. RISING/FALLING would be more canonical variable
names, but are reserved in the framework.
## Additional Context
My X4 has a terrible antenna, apparently, and I was running into this
failure condition pretty regularly. Wifi "bars" were chosen as a
relatively pan-cultural glyph rather than relying on localization.
Tested on hardware at -83 dBm under sustained EPUB upload (60 books, ~30
MB). Transient losses up to ~14s now ride through; pre-fix the same
losses required a power-cycle after as little as a 2s blip.
---
### AI Usage
While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.
Did you use AI tools to help write this code? Nope. Commits are hand
written. Claude was used to build a local test harness for validation
only during iteration.
Jeremy Klein