Update main.c to accept command line input

src/main.c

@@ -2,13 +2,20 @@
 #include "emu.h"
 #include "util.h"
 
-int main() {
+int main(int argc, char** argv) {
+
+    if (argc < 2) {
+        fprintf(stderr, "Usage: %s <ROM to emulate>\n", argv[0]);
+        return 1;
+    }
+
     Emulator* emu = initEmulator(0x00010FFF);
     if (!emu) {
         fprintf(stderr, "emu: error: failed to allocate memory for emulator\n");
         return 1;
     }
 
+    /*
     Instruction program[] = {
         {INST_MVI, {REG_A}, 0, true},
         {INST_MVI, {REG_B}, 123, true},
@@ -18,9 +25,18 @@ int main() {
     };
 
     memoryLoadProgram(emu->mem, program, sizeof(program)/sizeof(program[0]));
+    */
+
+    RomFile* rom = readProgramFromFile(argv[1]);
+    if (rom == NULL) {
+        fprintf(stderr, "Failed to read rom from %s\n", argv[1]);
+        return 1;
+    }
+
+    memoryLoadProgram(emu->mem, rom->instructions, rom->header.numInstructions);
 
     startEmulator(emu);
     freeEmulator(emu);
 
     return 0;
-}
+}