From a23c7321f53055549fbe9cbb9ab92dd059e6940b Mon Sep 17 00:00:00 2001
From: Peter Evans <peter@modul8r.com>
Date: Fri, 30 Mar 2018 16:26:24 -0500
Subject: [PATCH] Don't do certain operations if the drive is offline

---
 src/apple2.dd.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/src/apple2.dd.c b/src/apple2.dd.c
index 07d40fc..6accdc9 100644
--- a/src/apple2.dd.c
+++ b/src/apple2.dd.c
@@ -138,6 +138,7 @@ apple2_dd_insert(apple2dd *drive, FILE *stream, int type)
     // If we have any data, get rid of it. We'll start fresh here.
     apple2_dd_eject(drive);
 
+    drive->online = true;
     drive->image = vm_segment_create(finfo.st_size);
     drive->track_pos = 0;
     drive->sector_pos = 0;
@@ -439,8 +440,7 @@ apple2_dd_turn_on(apple2dd *drive, bool online)
 void
 apple2_dd_write(apple2dd *drive)
 {
-    // If there's no disk in the drive, then we can't write anything
-    if (drive->data == NULL) {
+    if (drive->data == NULL || !drive->online) {
         return;
     }
 
@@ -592,6 +592,10 @@ SEGMENT_READER(apple2_dd_switch_read)
     if (drive == NULL) {
         drive = mach->drive1;
     }
+
+    if (!drive->online) {
+        return 0x00;
+    }
     
     // In the first if block, we will handle 0x0..0x8; in the second if,
     // we'll do 0x9..0xB, 0xE, and 0xF.
@@ -633,6 +637,10 @@ SEGMENT_WRITER(apple2_dd_switch_write)
         drive = mach->drive1;
     }
     
+    if (!drive->online) {
+        return;
+    }
+    
     if (nib < 0x8) {
         apple2_dd_switch_phase(drive, nib);
     } else if (nib < 0xC || nib > 0xD) {