fix Win9x shutdown freeze after changing CD image

CHANGELOG

@@ -53,6 +53,8 @@
     Fixes corrupt graphics in the PC Booter version
     of Apple Panic. (Allofich)
   - Fixed possible crash with printing. (jamesbond3142)
+  - Fixed possible freeze when shutting down Windows 9x
+    after changing a CD image from the menu. (Wengier)
   - Fixed config option windowposition=x,y not working
     in Linux/macOS SDL1 builds. (Wengier)
   - Make memory B0000-B7FFF unmapped for the CGA

include/ide.h

@@ -13,6 +13,7 @@ extern void (*ide_inits[MAX_IDE_CONTROLLERS])(Section *);
 void IDE_Auto(signed char &index,bool &slave);
 void IDE_CDROM_Attach(signed char index,bool slave,unsigned char drive_index);
 void IDE_CDROM_Detach(unsigned char drive_index);
+void IDE_CDROM_Detach_Ret(signed char &indexret,bool &slaveret,unsigned char drive_index);
 void IDE_Hard_Disk_Attach(signed char index,bool slave,unsigned char bios_disk_index);
 void IDE_Hard_Disk_Detach(unsigned char bios_disk_index);
 void IDE_ResetDiskByBIOS(unsigned char disk);

src/dos/dos_programs.cpp

@@ -509,16 +509,22 @@ void MenuBrowseCDImage(char drive, int num) {
     lTheOpenFileName = tinyfd_openFileDialog("Select a CD image file","",14,lFilterPatterns,lFilterDescription,0);
 
     if (lTheOpenFileName) {
-        uint8_t mediaid = 0xF8;
-        int error = -1;
-        qmount = true;
-        DOS_Drive* newDrive = new isoDrive(drive, lTheOpenFileName, mediaid, error);
-        qmount = false;
-        if (error) {
-            tinyfd_messageBox("Error","Could not mount the selected CD image.","ok","error", 1);
-            return;
+        isoDrive *cdrom = dynamic_cast<isoDrive*>(Drives[drive-'A']);
+        DOS_Drive *newDrive = NULL;
+        if (cdrom && dos_kernel_disabled) {
+            cdrom->setFileName(lTheOpenFileName);
+        } else {
+            uint8_t mediaid = 0xF8;
+            int error = -1;
+            DOS_Drive* newDrive = new isoDrive(drive, lTheOpenFileName, mediaid, error);
+            if (error) {
+                tinyfd_messageBox("Error","Could not mount the selected CD image.","ok","error", 1);
+                chdir( Temp_CurrentDir );
+                return;
+            }
+            cdrom = dynamic_cast<isoDrive*>(newDrive);
         }
-        DriveManager::ChangeDisk(drive-'A', newDrive);
+        if (cdrom) DriveManager::ChangeDisk(drive-'A', cdrom);
 	}
 	chdir( Temp_CurrentDir );
 #endif
@@ -557,6 +563,7 @@ void MenuBrowseFDImage(char drive, int num, int type) {
         fatDrive *newDrive = new fatDrive(lTheOpenFileName, 0, 0, 0, 0, options);
         if (!newDrive->created_successfully) {
             tinyfd_messageBox("Error","Could not mount the selected floppy disk image.","ok","error", 1);
+            chdir( Temp_CurrentDir );
             return;
         }
         DriveManager::ChangeDisk(drive-'A', newDrive);

src/dos/drive_iso.cpp

@@ -192,6 +192,12 @@ isoDrive::isoDrive(char driveLetter, const char* fileName, uint8_t mediaid, int&
 
 isoDrive::~isoDrive() { }
 
+void isoDrive::setFileName(const char* fileName) {
+	safe_strncpy(this->fileName, fileName, CROSS_LEN);
+	strcpy(info, "isoDrive ");
+	strcat(info, fileName);
+}
+
 int isoDrive::UpdateMscdex(char driveLetter, const char* path, uint8_t& subUnit) {
 	if (MSCDEX_HasDrive(driveLetter)) {
 		subUnit = MSCDEX_GetSubUnit(driveLetter);

src/dos/drives.cpp

@@ -25,6 +25,7 @@
 #include "mapper.h"
 #include "support.h"
 #include "control.h"
+#include "ide.h"
 
 bool wild_match(const char *haystack, char *needle) {
 	size_t max, i;
@@ -279,6 +280,10 @@ void DriveManager::AppendDisk(int drive, DOS_Drive* disk) {
 void DriveManager::ChangeDisk(int drive, DOS_Drive* disk) {
     DriveInfo& driveInfo = driveInfos[drive];
     if (Drives[drive]==NULL||disk==NULL||!driveInfo.disks.size()) return;
+    isoDrive *cdrom = dynamic_cast<isoDrive*>(Drives[drive]);
+    bool slave=false;
+    signed char index=-1;
+    if (cdrom) IDE_CDROM_Detach_Ret(index,slave,drive);
     strcpy(disk->curdir,driveInfo.disks[driveInfo.currentDisk]->curdir);
     disk->Activate();
     disk->UpdateDPB(currentDrive);
@@ -287,6 +292,7 @@ void DriveManager::ChangeDisk(int drive, DOS_Drive* disk) {
     Drives[drive] = disk;
     Drives[drive]->EmptyCache();
     Drives[drive]->MediaChange();
+    if (cdrom && index>-1) IDE_CDROM_Attach(index,slave,drive);
     fatDrive *fdp = dynamic_cast<fatDrive*>(Drives[drive]);
     if (drive<2 && fdp && fdp->loadedDisk) {
         if (imageDiskList[drive]) {

src/dos/drives.h

@@ -662,6 +662,7 @@ public:
 	virtual bool isRemovable(void);
 	virtual Bits UnMount(void);
 	bool readSector(uint8_t *buffer, uint32_t sector);
+	void setFileName(const char* fileName);
 	virtual char const* GetLabel(void) {return discLabel;};
 	virtual void Activate(void);
 private:

src/hardware/ide.cpp

@@ -2265,6 +2265,24 @@ void IDE_CDROM_Detach(unsigned char drive_index) {
     }
 }
 
+void IDE_CDROM_Detach_Ret(signed char &indexret,bool &slaveret,unsigned char drive_index) {
+    indexret = -1;
+    for (int index = 0; index < MAX_IDE_CONTROLLERS; index++) {
+        IDEController *c = idecontroller[index];
+        if (c)
+        for (int slave = 0; slave < 2; slave++) {
+            IDEATAPICDROMDevice *dev;
+            dev = dynamic_cast<IDEATAPICDROMDevice*>(c->device[slave]);
+            if (dev && dev->drive_index == drive_index) {
+                delete dev;
+                c->device[slave] = NULL;
+                slaveret = slave;
+                indexret = index;
+            }
+        }
+    }
+}
+
 void IDE_CDROM_DetachAll() {
     for (int index = 0; index < MAX_IDE_CONTROLLERS; index++) {
         IDEController *c = idecontroller[index];