Device: Add disk read driver framework

Allow access to the device's logical disk.

At the moment, no drivers are implemented, so all devices have Access::None.

include/icsneo/disk/diskreaddriver.h

@@ -0,0 +1,47 @@
+#ifndef __DISKREADDRIVER_H__
+#define __DISKREADDRIVER_H__
+
+#ifdef __cplusplus
+
+#include "icsneo/platform/optional.h"
+#include "icsneo/communication/communication.h"
+#include "icsneo/api/eventmanager.h"
+#include <cstdint>
+#include <chrono>
+
+namespace icsneo {
+
+/**
+ * Interface for drivers which read block data from devices
+ */
+class DiskReadDriver {
+public:
+	static constexpr const std::chrono::milliseconds DefaultTimeout{2000};
+	static constexpr const size_t SectorSize = 512;
+	enum class Access {
+		None,
+		EntireCard,
+		VSA
+	};
+
+	virtual ~DiskReadDriver() = default;
+	virtual optional<uint64_t> readLogicalDisk(Communication& com, device_eventhandler_t report,
+		uint64_t pos, uint8_t* into, uint64_t amount, std::chrono::milliseconds timeout = DefaultTimeout);
+	virtual Access getAccess() const = 0;
+	virtual std::pair<uint32_t, uint32_t> getBlockSizeBounds() const = 0;
+
+protected:
+	/**
+	 * Perform a read which the driver can do in one shot.
+	 * 
+	 * The `pos` requested must be sector-aligned, and the `amount` must be
+	 * within the block size bounds provided by the driver.
+	 */
+	virtual optional<uint64_t> readLogicalDiskAligned(Communication& com, device_eventhandler_t report,
+		uint64_t pos, uint8_t* into, uint64_t amount, std::chrono::milliseconds timeout) = 0;
+};
+
+}
+
+#endif // __cplusplus
+#endif // __DISKREADDRIVER_H__

include/icsneo/disk/nulldiskreaddriver.h

@@ -0,0 +1,30 @@
+#ifndef __NULLDISKREADDRIVER_H__
+#define __NULLDISKREADDRIVER_H__
+
+#ifdef __cplusplus
+
+#include "icsneo/disk/diskreaddriver.h"
+
+namespace icsneo {
+
+/**
+ * A disk driver which always returns the requested disk as unsupported
+ * 
+ * Used for devices which do not have a disk, or do not provide any means for accessing it
+ */
+class NullDiskReadDriver : public DiskReadDriver {
+public:
+	optional<uint64_t> readLogicalDisk(Communication& com, device_eventhandler_t report,
+		uint64_t pos, uint8_t* into, uint64_t amount, std::chrono::milliseconds timeout = DefaultTimeout) override;
+	Access getAccess() const override { return Access::None; }
+	std::pair<uint32_t, uint32_t> getBlockSizeBounds() const override { return {SectorSize, SectorSize}; }
+
+private:
+	optional<uint64_t> readLogicalDiskAligned(Communication& com, device_eventhandler_t report,
+		uint64_t pos, uint8_t* into, uint64_t amount, std::chrono::milliseconds timeout) override;
+};
+
+}
+
+#endif // __cplusplus
+#endif // __NULLDISKREADDRIVER_H__