scsi: Fix CD media change not properly detected on some hosts

Tested with MSCDEX and SHSUCDX, without this change they do not detect the media change, and keep reporting the file system of the first loaded CD image.
If after changing image the user then attempts to navigate the new CD regardless, eventually the OS driver will get into a weird state and be unable to use the drive again.

src/BlueSCSI_Toolbox.cpp

@@ -211,7 +211,7 @@ void onSetNextCD(const char * img_dir)
     next_cd.getName(name, sizeof(name));
     next_cd.close();
     snprintf(full_path, (MAX_FILE_PATH * 2), "%s/%s", img_dir, name);
-    cdromSwitch(img, full_path);
+    cdromSwitchNextImage(img, full_path);
 }
 
 FsFile gFile; // global so we can keep it open while transferring.

src/BlueSCSI_cdrom.cpp

@@ -1181,7 +1181,7 @@ void cdromPerformEject(image_config_t &img)
         debuglog("------ CDROM open tray on ID ", (int)target);
         img.ejected = true;
         img.cdrom_events = 3; // Media removal
-        cdromSwitchNextImage(img); // Switch media for next time
+        cdromSwitchNextImage(img, nullptr); // Switch media for next time
     }
     else
     {
@@ -1199,7 +1199,7 @@ void cdromReinsertFirstImage(image_config_t &img)
         debuglog("---- Restarting from first CD-ROM image for ID ", (int)target);
         img.image_index = -1;
         img.current_image[0] = '\0';
-        cdromSwitchNextImage(img);
+        cdromSwitchNextImage(img, nullptr);
     }
     else if (img.ejected)
     {
@@ -1209,12 +1209,19 @@ void cdromReinsertFirstImage(image_config_t &img)
 }
 
 // Check if we have multiple CD-ROM images to cycle when drive is ejected.
-bool cdromSwitchNextImage(image_config_t &img)
+bool cdromSwitchNextImage(image_config_t &img, const char* next_filename)
 {
     // Check if we have a next image to load, so that drive is closed next time the host asks.
     char filename[MAX_FILE_PATH];
     int target_idx = img.scsiId & S2S_CFG_TARGET_ID_BITS;
-    scsiDiskGetNextImageName(img, filename, sizeof(filename));
+    if (next_filename == nullptr)
+    {
+        scsiDiskGetNextImageName(img, filename, sizeof(filename));
+    }
+    else
+    {
+        strncpy(filename, next_filename, MAX_FILE_PATH);
+    }
 
     if (filename[0] != '\0')
     {
@@ -1231,36 +1238,14 @@ bool cdromSwitchNextImage(image_config_t &img)
 
         if (status)
         {
-            return true;
-        }
-    }
-
-    return false;
-}
-
-// Check if we have multiple CD-ROM images to cycle when drive is ejected.
-bool cdromSwitch(image_config_t &img, const char* filename)
-{
-    // Check if we have a next image to load, so that drive is closed next time the host asks.
-    int target_idx = img.scsiId & S2S_CFG_TARGET_ID_BITS;
-
-    if (filename[0] != '\0')
-    {
-#ifdef ENABLE_AUDIO_OUTPUT
-        // if in progress for this device, terminate audio playback immediately (Annex C)
-        audio_stop(target_idx);
-        // Reset position tracking for the new image
-        audio_get_status_code(target_idx); // trash audio status code
-#endif
-        log("Switching to next CD-ROM image for ", target_idx, ": ", filename);
-        img.file.close();
-        int block_size = getBlockSize(const_cast<char*>(filename), target_idx, 2048);
-        bool status = scsiDiskOpenHDDImage(target_idx, filename, target_idx, 0, block_size);
-
-        if (status)
-        {
-            img.ejected = false;
-            img.cdrom_events = 2; // New media
+            if (next_filename != nullptr)
+            {
+                // present the drive as ejected until the host queries it again,
+                // to make sure host properly detects the media change
+                img.ejected = true;
+                img.reinsert_after_eject = true;
+                img.cdrom_events = 2; // New Media
+            }
             return true;
         }
     }

src/BlueSCSI_cdrom.h

@@ -22,7 +22,7 @@ void cdromPerformEject(image_config_t &img);
 void cdromReinsertFirstImage(image_config_t &img);
 
 // Switch to next CD-ROM image if multiple have been configured
-bool cdromSwitchNextImage(image_config_t &img);
+bool cdromSwitchNextImage(image_config_t &img, const char* filename);
 
 // Check if the currently loaded cue sheet for the image can be parsed
 // and print warnings about unsupported track types
@@ -32,6 +32,3 @@ bool cdromValidateCueSheet(image_config_t &img);
 // boolean flag is true if just basic mechanism status (playback true/false)
 // is desired, or false if historical audio status codes should be returned
 void cdromGetAudioPlaybackStatus(uint8_t *status, uint32_t *current_lba, bool current_only);
-
-// switch to a given filename for the cd.
-bool cdromSwitch(image_config_t &img, const char* filename);