From b2f018c11e1aa03bc2ed9326cf472cf048681392 Mon Sep 17 00:00:00 2001
From: SarahW <SarahW@localhost>
Date: Fri, 28 Apr 2017 18:13:03 +0100
Subject: [PATCH] HD loading can now autodetect some 17 sector MFM hard drives.
 Patch from Greatpsycho.

---
 src/allegro-gui-hdconf.c | 33 ++++++++++++++++++++++++++++++---
 src/win-hdconf.c         | 24 +++++++++++++++++++++---
 2 files changed, 51 insertions(+), 6 deletions(-)

diff --git a/src/allegro-gui-hdconf.c b/src/allegro-gui-hdconf.c
index 4021679..6f1809f 100644
--- a/src/allegro-gui-hdconf.c
+++ b/src/allegro-gui-hdconf.c
@@ -68,9 +68,36 @@ static int hdconf_open(int msg, DIALOG *d, int c)
                         fseeko64(f, -1, SEEK_END);
                         sz = ftello64(f) + 1;
                         fclose(f);
-                        sprintf(hd_sectors_new, "63");
-                        sprintf(hd_heads_new, "16");
-                        sprintf(hd_cylinders_new, "%i", (int)((sz / 512) / 16) / 63);
+                        if ((sz % 17) == 0 && sz <= 133693440)
+                        {
+                                sprintf(hd_sectors_new, "17");
+                                if (sz <= 26738688)
+                                {
+                                        sprintf(hd_heads_new, "4");
+                                        sprintf(hd_cylinders_new, "%i", (int)((sz / 512) / 4) / 17);
+                                }
+                                else if (sz <= 53477376)
+                                {
+                                        sprintf(hd_heads_new, "6");
+                                        sprintf(hd_cylinders_new, "%i", (int)((sz / 512) / 6) / 17);
+                                }
+                                else if (sz <= 71303168)
+                                {
+                                        sprintf(hd_heads_new, "8");
+                                        sprintf(hd_cylinders_new, "%i", (int)((sz / 512) / 8) / 17);
+                                }
+                                else
+                                {
+                                        sprintf(hd_heads_new, "15");
+                                        sprintf(hd_cylinders_new, "%i", (int)((sz / 512) / 15) / 17);
+                                }
+                        }
+                        else
+                        {
+                                sprintf(hd_sectors_new, "63");
+                                sprintf(hd_heads_new, "16");
+                                sprintf(hd_cylinders_new, "%i", (int)((sz / 512) / 16) / 63);
+                        }
 
                         while (1)
                         {
diff --git a/src/win-hdconf.c b/src/win-hdconf.c
index ffeb33c..add5e40 100644
--- a/src/win-hdconf.c
+++ b/src/win-hdconf.c
@@ -61,9 +61,27 @@ static void check_hd_type(off64_t sz)
         }
         else
         {
-                hd_new_spt = 63;
-                hd_new_hpc = 16;
-                hd_new_cyl = ((sz / 512) / 16) / 63;
+                if ((sz % 17) == 0 && sz <= 133693440)
+                {
+                        hd_new_spt = 17;
+
+                        if (sz <= 26738688)
+                                hd_new_hpc = 4;
+                        else if (sz <= 53477376)
+                                hd_new_hpc = 6;
+                        else if (sz <= 71303168)
+                                hd_new_hpc = 8;
+                        else
+                                hd_new_hpc = 15;
+
+                        hd_new_cyl = (int)((sz / 512) / hd_new_hpc) / 17;
+                }
+                else
+                {
+                        hd_new_spt = 63;
+                        hd_new_hpc = 16;
+                        hd_new_cyl = ((sz / 512) / 16) / 63;
+                }
         }
 }