initial build system tweaks for pico hardware

src/avclan/target/avr-attiny3216/CMakeLists.txt

@@ -12,6 +12,11 @@ target_sources(avclan PRIVATE
     )
 
 target_include_directories(avclan PUBLIC ${CMAKE_CURRENT_SOURCE_DIR})
+target_compile_options(avclan PUBLIC
+    $<$<COMPILE_LANGUAGE:CXX>:-fno-threadsafe-statics>
+    $<$<COMPILE_LANGUAGE:CXX>:-fno-exceptions>
+    $<$<COMPILE_LANGUAGE:CXX>:-fno-rtti>
+)
 
 find_program(AVRDUDE avrdude)
 set(AVR_PROGRAMMER serialupdi CACHE STRING "avrdude programmer hardware")
@@ -76,9 +81,6 @@ set_property(CACHE USART_RXMODE PROPERTY STRINGS
 # tick. 1000 = no correction; set per-board in CMakeUserPresets.json.
 set(RTC_STATUS_PERIOD_MS 1000 CACHE STRING "Measured ms per nominal RTC status period (1000 = no correction)")
 
-# --- Firmware configuration options ----------------------------------------
-set(AVCLAN_FRAME_POOL_N 14 CACHE STRING "Pool allocator capacity for avclan::Frame (must be <= incoming/outgoing queue size)")
-
 try_compile(LIBC_VERSION_TEST
     SOURCES "${CMAKE_SOURCE_DIR}/cmake/libc-version-test.cpp"
     COMPILE_DEFINITIONS -mmcu=${AVR_MCU}

src/sniffer.cc

@@ -20,7 +20,7 @@
 
 const char *const offon[] = {"OFF", "ON"};
 
-constexpr uint8_t CACHE_SIZE = 16;
+constexpr uint8_t CACHE_SIZE = AVCLAN_MSG_QUEUE_SIZE;
 static_assert(CACHE_SIZE >= AVCLAN_FRAME_POOL_N,
               "CACHE_SIZE must be >= avclan::Frame allocator pool capacity");