Added guards against accessing out-of-bounds floppy drives.

src/disc.c

@@ -125,7 +125,7 @@ int disc_hole(int drive)
 {
 	drive ^= fdd_swap;
 
-	if (drives[drive].hole)
+	if (drive < 2 && drives[drive].hole)
 	{
 		return drives[drive].hole(drive);
 	}
@@ -139,7 +139,7 @@ void disc_poll()
 {
         disc_poll_time += disc_period * TIMER_USEC;
 
-        if (drives[disc_drivesel].poll)
+        if (disc_drivesel < 2 && drives[disc_drivesel].poll)
                 drives[disc_drivesel].poll();
 
         if (disc_notfound)
@@ -228,10 +228,6 @@ void disc_reset()
 
 void disc_init()
 {
-//        pclog("disc_init %p\n", drives);
-        drives[0].poll = drives[1].poll = 0;
-        drives[0].seek = drives[1].seek = 0;
-        drives[0].readsector = drives[1].readsector = 0;
         disc_reset();
 }
 
@@ -239,7 +235,7 @@ int oldtrack[2] = {0, 0};
 void disc_seek(int drive, int track)
 {
 //        pclog("disc_seek: drive=%i track=%i\n", drive, track);
-        if (drives[drive].seek)
+        if (drive < 2 && drives[drive].seek)
                 drives[drive].seek(drive, track);
 //        if (track != oldtrack[drive])
 //                fdc_discchange_clear(drive);
@@ -251,7 +247,7 @@ void disc_readsector(int drive, int sector, int track, int side, int density, in
 {
         drive ^= fdd_swap;
 
-        if (drives[drive].readsector)
+        if (drive < 2 && drives[drive].readsector)
                 drives[drive].readsector(drive, sector, track, side, density, sector_size);
         else
                 disc_notfound = 1000;
@@ -261,7 +257,7 @@ void disc_writesector(int drive, int sector, int track, int side, int density, i
 {
         drive ^= fdd_swap;
 
-        if (drives[drive].writesector)
+        if (drive < 2 && drives[drive].writesector)
                 drives[drive].writesector(drive, sector, track, side, density, sector_size);
         else
                 disc_notfound = 1000;
@@ -271,7 +267,7 @@ void disc_readaddress(int drive, int track, int side, int density)
 {
         drive ^= fdd_swap;
 
-        if (drives[drive].readaddress)
+        if (drive < 2 && drives[drive].readaddress)
                 drives[drive].readaddress(drive, track, side, density);
 }
 
@@ -279,7 +275,7 @@ void disc_format(int drive, int track, int side, int density, uint8_t fill)
 {
         drive ^= fdd_swap;
         
-        if (drives[drive].format)
+        if (drive < 2 && drives[drive].format)
                 drives[drive].format(drive, track, side, density, fill);
         else
                 disc_notfound = 1000;
@@ -289,7 +285,7 @@ void disc_stop(int drive)
 {
         drive ^= fdd_swap;
         
-        if (drives[drive].stop)
+        if (drive < 2 && drives[drive].stop)
                 drives[drive].stop(drive);
 }
 

src/fdd.c

@@ -79,6 +79,9 @@ int fdd_swap = 0;
 void fdd_seek(int drive, int track_diff)
 {
         drive ^= fdd_swap;
+        
+        if (drive >= 2)
+                return;
 
         fdd[drive].track += track_diff;
         
@@ -101,13 +104,17 @@ void fdd_disc_changed(int drive)
         drive ^= fdd_swap;
         
         /*Force reload of current track data*/
-        disc_seek(drive, fdd[drive].track);
+        if (drive < 2)
+                disc_seek(drive, fdd[drive].track);
 }
 
 int fdd_track0(int drive)
 {
         drive ^= fdd_swap;
 
+        if (drive >= 2)
+                return 0;
+
 	/* If drive is disabled, TRK0 never gets set. */
 	if (!drive_types[fdd[drive].type].max_track)  return 0;
 
@@ -122,9 +129,14 @@ void fdd_set_densel(int densel)
 
 int fdd_getrpm(int drive)
 {
-	int hole = disc_hole(drive);
+	int hole;
 
         drive ^= fdd_swap;
+        
+        if (drive >= 2)
+                return 0;
+
+        hole = disc_hole(drive);
 
 	if (!(drive_types[fdd[drive].type].flags & FLAG_RPM_360))  return 300;
 	if (!(drive_types[fdd[drive].type].flags & FLAG_RPM_300))  return 360;
@@ -162,9 +174,14 @@ void fdd_setswap(int swap)
 
 int fdd_can_read_medium(int drive)
 {
-	int hole = disc_hole(drive);
+	int hole;
 
 	drive ^= fdd_swap;
+        
+        if (drive >= 2)
+                return 0;
+
+        hole = disc_hole(drive);
 
 	hole = 1 << (hole + 3);
 
@@ -174,25 +191,34 @@ int fdd_can_read_medium(int drive)
 
 int fdd_doublestep_40(int drive)
 {
+        if (drive >= 2)
+                return 0;
         return drive_types[fdd[drive].type].flags & FLAG_DOUBLE_STEP;
 }
 
 void fdd_set_type(int drive, int type)
 {
-	fdd[drive].type = type;
+        if (drive < 2)
+        	fdd[drive].type = type;
 }
 
 int fdd_get_type(int drive)
 {
+        if (drive >= 2)
+                return 0;
 	return fdd[drive].type;
 }
 
 int fdd_is_525(int drive)
 {
+        if (drive >= 2)
+                return 0;
         return drive_types[fdd[drive].type].flags & FLAG_525;
 }
 
 int fdd_is_ed(int drive)
 {
+        if (drive >= 2)
+                return 0;
         return drive_types[fdd[drive].type].flags & FLAG_HOLE2;
 }