LF only, more FS fixes

src/file.c

@@ -6,12 +6,12 @@
 // Up to 256 files can be open
 FILE *files[256];
 
-int openFile(int fd, const char *path) {
+int openFile(int fd, const char *path, const char *mode) {
   if (files[fd] != NULL) {
     return STATUS_READY | STATUS_ERROR;
   }
 
-  files[fd] = fopen(path, "w+");
+  files[fd] = fopen(path, mode);
   if (files[fd] == NULL) {
     return STATUS_READY | STATUS_ERROR;
   }
@@ -36,9 +36,9 @@ int closeFile(int fd) {
   return STATUS_READY;
 }
 
-int readByte(const int fd, int *data) {
+int readByte(const int fd, uint8_t *data) {
   int status = 0;
-  int count = fread(&data, 1, 1, files[fd]);
+  int count = fread(data, 1, 1, files[fd]);
   // Error or EOF
   if (count != 1) {
     int error = ferror(files[fd]);
@@ -53,7 +53,7 @@ int readByte(const int fd, int *data) {
   return STATUS_READY | status;
 }
 
-int writeByte(const int fd, const int data) {
+int writeByte(const int fd, const uint8_t data) {
   int status = 0;
   int count = fwrite(&data, 1, 1, files[fd]);
   // Error or EOF