* fix(native): implement BinarySemaphorePosix with proper pthread synchronization
The BinarySemaphorePosix class (used on all Linux/portduino/native builds)
had stub implementations: give() was a no-op and take() just called
delay(msec) and returned false. This broke the cooperative thread scheduler
on native platforms — threads could not wake the main loop, radio RX
interrupts were missed, and telemetry never transmitted over the mesh.
Replace the stubs with a proper binary semaphore using pthread_mutex_t +
pthread_cond_t + bool signaled:
- take(msec): pthread_cond_timedwait with CLOCK_REALTIME timeout, consumes
signal atomically (binary semaphore semantics)
- give(): sets signaled=true, signals condition variable
- giveFromISR(): delegates to give(), sets pxHigherPriorityTaskWoken
Tested on Raspberry Pi 3 Model B (ARM64, Debian Bookworm) with Adafruit
LoRa Radio Bonnet (SX1276). Before fix: no radio TX/RX, no telemetry on
mesh. After fix: bidirectional LoRa, MQTT gateway, telemetry all working.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
* ARCH_PORTDUINO
* Refactor BinarySemaphorePosix header for ARCH_PORTDUINO
* Change preprocessor directive from ifndef to ifdef
* Gate new Semaphore code to Portduino and fix STM compilation
* Binary Semaphore Posix better error handling
---------
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
Co-authored-by: Ben Meadors <benmmeadors@gmail.com>
Co-authored-by: Jonathan Bennett <jbennett@incomsystems.biz>
