EEPROM file storage, and argparsing that actually works

simulation/src/simeeprom.cpp

@@ -8,6 +8,8 @@
 
 EEPROMClass::EEPROMClass() {
     memset(someFakeEEPROM_memory, 0xff, sizeof(someFakeEEPROM_memory));
+    storage = NULL;
+    autoUpdate = false;
 }
 
 
@@ -22,15 +24,98 @@ void  EEPROMClass::write( int idx, uint8_t val )
 {
     printf("Writing to EEPROM address %u = %u\n", idx, val);
     someFakeEEPROM_memory[idx] = val;
+
+    if(autoUpdate && storage)
+    {
+        fseek(storage, idx, SEEK_SET);
+        fputc(val, storage);
+        fflush(storage);
+    }
 }
 
 void  EEPROMClass::update( int idx, uint8_t val )
 {
     write(idx, val);
 }
+
 uint16_t EEPROMClass::length()
 {
     return sizeof(someFakeEEPROM_memory);
 }
 
-// TODO: Add missing functioality..
+int16_t EEPROMClass::setStorage(const char* filename, bool write)
+{
+
+	//Close any open storage file
+	if(storage)
+	{
+		fclose(storage);
+		storage = NULL;
+	}
+
+    autoUpdate = write;
+
+	storage = fopen(filename, "rb");
+	
+
+    //If only reading, fail if file does not exist (makes no sense otherwise)
+    if(!storage && !autoUpdate) {
+		printf("Could not open EEPROM storage file: '%s'\n", filename);
+		return -1;
+	}
+
+    if(storage)
+    {
+        printf("Reading EEPROM storage file: '%s'\n", filename);
+        rewind(storage);
+        fread(someFakeEEPROM_memory, sizeof(someFakeEEPROM_memory), 1, storage);
+    }
+
+    if(!autoUpdate)
+    {
+        //No need for the file anymore, close it
+        fclose(storage);
+        storage = NULL;
+    }
+
+    //Create file if it doesn't exist (so we can write to it)
+    if(!storage && autoUpdate)
+    {
+        storage = fopen(filename, "wb");
+        if(!storage)
+        {
+            printf("Could not create EEPROM storage file: '%s'\n", filename);
+            autoUpdate = false;
+            return -2;
+        }
+    }
+
+    if(storage && autoUpdate)
+    {
+        //Reopen file for writing without overwriting it
+        storage = freopen(filename, "r+b", storage);
+
+        if(!storage)
+        {
+            printf("Could not access EEPROM storage file for writing: '%s'\n", filename);
+            autoUpdate = false;
+            return -3;
+        }
+
+        printf("Writing any EEPROM changes to '%s'\n", filename);
+    }
+
+    return 0;
+}
+
+void EEPROMClass::closeStorage() {
+    if(storage==NULL)
+    {
+        return;
+    }
+
+    printf("Closing EEPROM storage\n");
+
+    fclose(storage);
+    storage=NULL;
+}