fix segmentation fault when --led-emulator is set via command line

Author: sshcrack

CMakeLists.txt

@@ -29,13 +29,7 @@ set(MATRIX_SOURCES ${MATRIX_CORE_SOURCES})
 if(ENABLE_EMULATOR)
     # Add emulator source
     list(APPEND MATRIX_SOURCES lib/emulator.cc)
-    
-    # Find SDL2 for the emulator
-    find_package(SDL2 REQUIRED)
-    
-    # Define preprocessor macro to indicate emulator is enabled
-    add_compile_definitions(ENABLE_EMULATOR)
-    
+
     message(STATUS "Building with emulator support")
 else()
     message(STATUS "Building without emulator support")
@@ -49,11 +43,20 @@ target_compile_features(${PROJECT_NAME} PRIVATE cxx_std_14)
 # Include directories
 target_include_directories(${PROJECT_NAME}
     PRIVATE
-        # where the library itself will look for its internal headers
-        ${CMAKE_CURRENT_SOURCE_DIR}/lib
+    # where the library itself will look for its internal headers
+    ${CMAKE_CURRENT_SOURCE_DIR}/lib
     PUBLIC
-        # where top-level project will look for the library's public headers
-        $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>
-        # where external projects will look for the library's public headers
-        $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>
+    # where top-level project will look for the library's public headers
+    $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>
+    # where external projects will look for the library's public headers
+    $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>
 )
+
+# Export ENABLE_EMULATOR define to consumers of the library
+if(ENABLE_EMULATOR)
+    target_compile_definitions(${PROJECT_NAME} PUBLIC ENABLE_EMULATOR)
+
+    # Find SDL2 for the emulator
+    find_package(SDL2 REQUIRED)
+    target_link_libraries(${PROJECT_NAME} PRIVATE SDL2)
+endif()

examples/emulator-demo.cc

@@ -50,7 +50,6 @@ int main(int argc, char *argv[]) {
   options.led_options.chain_length = 2;
   options.led_options.parallel = 2;
   options.led_options.hardware_mapping = "regular";  // Add this line to ensure hardware mapping is set
-  options.use_emulator = true;
   options.emulator_options.display_scale = 5;  // Larger window for emulator
   options.emulator_options.window_title = "LED Matrix Emulator Demo";
 

include/matrix-factory.h

@@ -17,7 +17,11 @@
 #define RPI_RGBMATRIX_FACTORY_H
 
 #include "led-matrix.h"
+
+// Only include emulator.h when emulator support is enabled
+#ifdef ENABLE_EMULATOR
 #include "emulator.h"
+#endif
 
 namespace rgb_matrix {
 
@@ -38,7 +42,6 @@ class MatrixFactory {
     // Runtime options specific to the hardware matrix
     RuntimeOptions runtime_options;
 
-
 #ifdef ENABLE_EMULATOR
     // Options specific to the emulator
     EmulatorOptions emulator_options;

lib/matrix-factory.cc

@@ -69,7 +69,8 @@ namespace rgb_matrix
                 options->use_emulator = true;
                 if (remove_consumed_flags)
                 {
-                    (*argv)[i] = nullptr;
+                    // Very unclean way of doing this, but it works
+                    (*argv)[i] = "";
                 }
             }
         }