ci: update AVR toolchain installation and add simulation steps for testing

Author: gooderfreed

.github/workflows/ci.yml

@@ -275,13 +275,30 @@ jobs:
         opt: [-O0, -O1, -O2, -O3, -Os]
     steps:
       - uses: actions/checkout@v6
-      - name: install-avr-toolchain
-        run: sudo apt-get update && sudo apt-get install -y gcc-avr avr-libc
-      - name: compile-library-no-malloc
+      
+      - name: install-avr-toolchain-and-simulator
+        run: sudo apt-get update && sudo apt-get install -y gcc-avr avr-libc simavr
+        
+      - name: compile-library-and-print-size
         run: |
+          # Compile the isolated library object file to check standalone footprint
           avr-gcc -mmcu=atmega328p ${{ matrix.opt }} -Wall -Wextra -Werror \
             -Wshadow -Wconversion -Wsign-conversion -Wcast-align \
-            -DESTACK_NO_MALLOC -DESTACK_NO_AUTO_ALIGN -DEASY_STACK_IMPLEMENTATION \
+            -DESTACK_NO_MALLOC -DEASY_STACK_IMPLEMENTATION \
             -x c -c easy_stack.h -o easy_stack.o
-      - name: verify-binary-size
-        run: avr-size easy_stack.o
+            
+          echo "=== Standalone Library Footprint ==="
+          avr-size easy_stack.o
+        
+      - name: compile-and-run-avr-simulation
+        run: |
+          # Compile the standalone AVR test for ATmega328P
+          avr-gcc -mmcu=atmega328p ${{ matrix.opt }} -Wall -Wextra -Werror \
+            -Wshadow -Wconversion -Wsign-conversion -Wcast-align \
+            -I. tests/avr_test.c -o avr_test.elf
+            
+          echo "=== Full Test Binary Footprint ==="
+          avr-size avr_test.elf
+            
+          # Run the test binary inside the simavr emulator
+          simavr -m atmega328p avr_test.elf

Makefile

@@ -53,7 +53,8 @@ export UBSAN_OPTIONS=halt_on_error=0:exitcode=1:print_stacktrace=1
 export ASAN_OPTIONS=$(ASAN_OPTS)
 
 TEST_DIR = tests
-TEST_SRCS = $(wildcard $(TEST_DIR)/*.c)
+# Collect all tests except the specialized AVR bare-metal simulation
+TEST_SRCS = $(filter-out $(TEST_DIR)/avr_test.c, $(wildcard $(TEST_DIR)/*.c))
 # Generate names for coverage object files
 TEST_COV_OBJS = $(TEST_SRCS:$(TEST_DIR)/%.c=$(TEST_DIR)/%.cov.o)
 # Generate names for coverage executables

tests/avr_test.c

@@ -0,0 +1,55 @@
+#define EASY_STACK_IMPLEMENTATION
+#define ESTACK_NO_MALLOC
+#include "easy_stack.h"
+#include <stdlib.h>
+
+/*
+ * Standalone assertion helper for bare-metal AVR environment.
+ * If the condition fails, we trigger abort() which halts simavr with an error.
+ */
+static void avr_assert(bool condition) {
+    if (!condition) {
+        abort();
+    }
+}
+
+int main(void) {
+    // 1. Initialize a small static buffer (128 bytes)
+    uint8_t pool[128];
+    EStack *stack = estack_create_static(pool, sizeof(pool));
+    
+    avr_assert(stack != NULL);
+    avr_assert(estack_get_meta_index(stack) == 0);
+    avr_assert(estack_get_meta_type(stack) == 0); // Must use uint8_t offsets
+    
+    // 2. Test basic allocation (default word alignment on AVR is 2 bytes)
+    void *p1 = estack_alloc(stack, 10);
+    avr_assert(p1 != NULL);
+    avr_assert(estack_get_meta_index(stack) == 1);
+    avr_assert(((uintptr_t)p1 % 2) == 0);
+    
+    // 3. Test power-of-two alignment (requesting 4-byte boundary on 16-bit system)
+    void *p2 = estack_alloc_aligned(stack, 15, 4);
+    avr_assert(p2 != NULL);
+    avr_assert(((uintptr_t)p2 % 4) == 0);
+    
+    // 4. Test LIFO deallocation
+    estack_free(stack, p2);
+    estack_free(stack, p1);
+    avr_assert(estack_get_meta_index(stack) == 0);
+    
+    // 5. Test Stack Marker Rollbacks
+    void *t1 = estack_alloc(stack, 8);
+    EStackMarker marker = estack_get_marker(stack);
+    
+    void *t2 = estack_alloc(stack, 16);
+    avr_assert(estack_get_meta_index(stack) == 2);
+    
+    estack_free_to_marker(stack, marker);
+    avr_assert(estack_get_meta_index(stack) == 1);
+    
+    estack_free(stack, t1);
+    avr_assert(estack_get_meta_index(stack) == 0);
+    
+    return 0; // Success
+}