Be friendlier when trying to but from empty DVD drives.

git-svn-id: https://dolphin-emu.googlecode.com/svn/trunk@2422 8ced0084-cf51-0410-be5f-012b33b47a6e

Source/Core/DiscIO/Src/Blob.cpp

@@ -131,7 +131,7 @@ IBlobReader* CreateBlobReader(const char* filename)
 	if (IsCompressedBlob(filename))
 		return CompressedBlobReader::Create(filename);
 
-	// Still here? Assume plain file.
+	// Still here? Assume plain file - since we know it exists due to the File::Exists check above.
 	return PlainFileReader::Create(filename);
 }
 

Source/Core/DiscIO/Src/DriveBlob.cpp

@@ -21,17 +21,28 @@
 namespace DiscIO
 {
 	DriveReader::DriveReader(const char *drive)
+		: hDisc(INVALID_HANDLE_VALUE)
 	{
 #ifdef _WIN32
 		char path[MAX_PATH];
 		strncpy(path, drive, 3);
 		path[2] = 0;
 		sprintf(path, "\\\\.\\%s", drive);
-
+		SectorReader::SetSectorSize(2048);
 		hDisc = CreateFile(path, GENERIC_READ, FILE_SHARE_READ | FILE_SHARE_WRITE,
 							NULL, OPEN_EXISTING, FILE_FLAG_RANDOM_ACCESS, NULL);
 		if (hDisc != INVALID_HANDLE_VALUE)
 		{
+			// Do a test read to make sure everything is OK, since it seems you can get
+			// handles to empty drives.
+			DWORD not_used;
+			if (!ReadFile(hDisc, 0, m_blocksize, (LPDWORD)&not_used, NULL))
+			{
+				// OK, something is wrong.
+				CloseHandle(hDisc);
+				hDisc = INVALID_HANDLE_VALUE;
+				return;
+			}
 			
 		#ifdef _LOCKDRIVE // Do we want to lock the drive?
 			// Lock the compact disc in the CD-ROM drive to prevent accidental
@@ -46,7 +57,6 @@ namespace DiscIO
 		if (file_)
 		{
 #endif
-			SectorReader::SetSectorSize(2048);
 		}
 		else
 		{
@@ -67,15 +77,23 @@ namespace DiscIO
 		if (hDisc != INVALID_HANDLE_VALUE)
 		{
 			CloseHandle(hDisc);
+			hDisc = INVALID_HANDLE_VALUE;
 		}
 #else
 		fclose(file_);
+		file_ = 0;
 #endif	
 	}
 
 	DriveReader *DriveReader::Create(const char *drive)
 	{
-		return new DriveReader(drive);
+		DriveReader *reader = new DriveReader(drive);
+		if (!reader->IsOK())
+		{
+			delete reader;
+			return 0;
+		}
+		return reader;
 	}
 
 	void DriveReader::GetBlock(u64 block_num, u8 *out_ptr)
@@ -88,7 +106,7 @@ namespace DiscIO
 		LONG off_high = (LONG)(offset >> 32);
 		SetFilePointer(hDisc, off_low, &off_high, FILE_BEGIN);
 		if (!ReadFile(hDisc, lpSector, m_blocksize, (LPDWORD)&NotUsed, NULL))
-			PanicAlert("DRE");
+			PanicAlert("Disc Read Error");
 #else
 		fseek(file_, m_blocksize*block_num, SEEK_SET);
 		fread(lpSector, 1, m_blocksize, file_);
@@ -107,7 +125,7 @@ namespace DiscIO
 		SetFilePointer(hDisc, off_low, &off_high, FILE_BEGIN);
 		if (!ReadFile(hDisc, out_ptr, (DWORD)(m_blocksize * num_blocks), (LPDWORD)&NotUsed, NULL))
 		{
-			PanicAlert("DRE");
+			PanicAlert("Disc Read Error");
 			return false;
 		}
 #else

Source/Core/DiscIO/Src/DriveBlob.h

@@ -37,8 +37,10 @@ private:
 #ifdef _WIN32
 	HANDLE hDisc;
 	PREVENT_MEDIA_REMOVAL pmrLockCDROM;
+	bool IsOK() {return hDisc != INVALID_HANDLE_VALUE;}
 #else
 	FILE* file_;
+	bool IsOK() {return file_ != 0;}
 #endif
 	s64 size;
 	u64 *block_pointers;

Source/Core/DiscIO/Src/VolumeCreator.cpp

@@ -93,7 +93,7 @@ IVolume* CreateVolumeFromFilename(const std::string& _rFilename)
 				delete pReader;
 			}
 
-			return(pVolume);
+			return pVolume;
 		}
 			break;
 
@@ -137,7 +137,7 @@ IVolume* CreateVolumeFromCryptedWiiImage(IBlobReader& _rReader, u32 _VolumeType,
 				"'%s' before pressing [YES].", MasterKeyFile, MasterKeyFileHex))
 			{
 				pT = fopen(MasterKeyFileHex, "r");
-				if(pT==NULL){
+				if (!pT) {
 					PanicAlert("could not open %s", MasterKeyFileHex);
 					return NULL;
 				}
@@ -160,7 +160,7 @@ IVolume* CreateVolumeFromCryptedWiiImage(IBlobReader& _rReader, u32 _VolumeType,
 				}
 
 				pT = fopen(MasterKeyFile, "wb");
-				if(pT==NULL){
+				if (!pT) {
 					PanicAlert("could not open/make '%s' for writing!", MasterKeyFile);
 					return NULL;
 				}
@@ -169,7 +169,7 @@ IVolume* CreateVolumeFromCryptedWiiImage(IBlobReader& _rReader, u32 _VolumeType,
 				fclose(pT);
 
 				pT = fopen(MasterKeyFileHex, "rb");
-				if(pT==NULL){
+				if (!pT) {
 					PanicAlert("could not open '%s' for reading!\n did the file get deleted or locked after converting?", MasterKeyFileHex);
 					return NULL;
 				}